| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.util.regex; |
| |
| import android.compat.Compatibility; |
| import android.compat.annotation.ChangeId; |
| import android.compat.annotation.EnabledSince; |
| |
| import com.android.icu.util.regex.PatternNative; |
| |
| import dalvik.annotation.compat.VersionCodes; |
| import dalvik.system.VMRuntime; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.NoSuchElementException; |
| import java.util.Spliterator; |
| import java.util.Spliterators; |
| import java.util.function.Predicate; |
| import java.util.stream.Stream; |
| import java.util.stream.StreamSupport; |
| import libcore.util.EmptyArray; |
| |
| // Android-changed: Document that named capturing is only available from API 26. |
| // Android-changed: Android always uses unicode character classes. |
| // Android-changed: Remove reference to Character.codePointOf(String) until it's implemented. |
| // Android-changed: UNICODE_CHARACTER_CLASS causes IllegalArgumentException on Android. |
| // Android-changed: POSIX character classes are Unicode-aware. |
| // Android-changed: Throw PatternSyntaxException for non-existent back references. |
| // Android-changed: Remove "Compatibility Properties of Unicode Regular Expression" table. |
| // Android-changed: Remove supported \b{g} Unicode extended grapheme cluster boundary. |
| // Android-changed: Prefix "Is" is supported since Android 10. http://b/110364810 |
| /** |
| * A compiled representation of a regular expression. |
| * |
| * <p> A regular expression, specified as a string, must first be compiled into |
| * an instance of this class. The resulting pattern can then be used to create |
| * a {@link Matcher} object that can match arbitrary {@linkplain |
| * java.lang.CharSequence character sequences} against the regular |
| * expression. All of the state involved in performing a match resides in the |
| * matcher, so many matchers can share the same pattern. |
| * |
| * <p> A typical invocation sequence is thus |
| * |
| * <blockquote><pre> |
| * Pattern p = Pattern.{@link #compile compile}("a*b"); |
| * Matcher m = p.{@link #matcher matcher}("aaaaab"); |
| * boolean b = m.{@link Matcher#matches matches}();</pre></blockquote> |
| * |
| * <p> A {@link #matches matches} method is defined by this class as a |
| * convenience for when a regular expression is used just once. This method |
| * compiles an expression and matches an input sequence against it in a single |
| * invocation. The statement |
| * |
| * <blockquote><pre> |
| * boolean b = Pattern.matches("a*b", "aaaaab");</pre></blockquote> |
| * |
| * is equivalent to the three statements above, though for repeated matches it |
| * is less efficient since it does not allow the compiled pattern to be reused. |
| * |
| * <p> Instances of this class are immutable and are safe for use by multiple |
| * concurrent threads. Instances of the {@link Matcher} class are not safe for |
| * such use. |
| * |
| * |
| * <h2><a id="sum">Summary of regular-expression constructs</a></h2> |
| * |
| * <table class="borderless"> |
| * <caption style="display:none">Regular expression constructs, and what they match</caption> |
| * <thead style="text-align:left"> |
| * <tr> |
| * <th id="construct">Construct</th> |
| * <th id="matches">Matches</th> |
| * </tr> |
| * </thead> |
| * <tbody style="text-align:left"> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="characters">Characters</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight: normal" id="x"><i>x</i></th> |
| * <td headers="matches characters x">The character <i>x</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="backslash">{@code \\}</th> |
| * <td headers="matches characters backslash">The backslash character</td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="octal_n">{@code \0}<i>n</i></th> |
| * <td headers="matches characters octal_n">The character with octal value {@code 0}<i>n</i> |
| * (0 {@code <=} <i>n</i> {@code <=} 7)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="octal_nn">{@code \0}<i>nn</i></th> |
| * <td headers="matches characters octal_nn">The character with octal value {@code 0}<i>nn</i> |
| * (0 {@code <=} <i>n</i> {@code <=} 7)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="octal_nnn">{@code \0}<i>mnn</i></th> |
| * <td headers="matches characters octal_nnn">The character with octal value {@code 0}<i>mnn</i> |
| * (0 {@code <=} <i>m</i> {@code <=} 3, |
| * 0 {@code <=} <i>n</i> {@code <=} 7)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="hex_hh">{@code \x}<i>hh</i></th> |
| * <td headers="matches characters hex_hh">The character with hexadecimal value {@code 0x}<i>hh</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="hex_hhhh"><code>\u</code><i>hhhh</i></th> |
| * <td headers="matches characters hex_hhhh">The character with hexadecimal value {@code 0x}<i>hhhh</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="hex_h_h"><code>\x</code><i>{h...h}</i></th> |
| * <td headers="matches characters hex_h_h">The character with hexadecimal value {@code 0x}<i>h...h</i> |
| * ({@link java.lang.Character#MIN_CODE_POINT Character.MIN_CODE_POINT} |
| * <= {@code 0x}<i>h...h</i> <= |
| * {@link java.lang.Character#MAX_CODE_POINT Character.MAX_CODE_POINT})</td></tr> |
| * <tr><th style="vertical-align:top; font-weight: normal" id="unicode_name"><code>\N{</code><i>name</i><code>}</code></th> |
| * <td headers="matches characters unicode_name">The character with Unicode character name <i>'name'</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="tab">{@code \t}</th> |
| * <td headers="matches characters tab">The tab character (<code>'\u0009'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="newline">{@code \n}</th> |
| * <td headers="matches characters newline">The newline (line feed) character (<code>'\u000A'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="return">{@code \r}</th> |
| * <td headers="matches characters return">The carriage-return character (<code>'\u000D'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="form_feed">{@code \f}</th> |
| * <td headers="matches characters form_feed">The form-feed character (<code>'\u000C'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="bell">{@code \a}</th> |
| * <td headers="matches characters bell">The alert (bell) character (<code>'\u0007'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="escape">{@code \e}</th> |
| * <td headers="matches characters escape">The escape character (<code>'\u001B'</code>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="ctrl_x">{@code \c}<i>x</i></th> |
| * <td headers="matches characters ctrl_x">The control character corresponding to <i>x</i></td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="classes">Character classes</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="simple">{@code [abc]}</th> |
| * <td headers="matches classes simple">{@code a}, {@code b}, or {@code c} (simple class)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="negation">{@code [^abc]}</th> |
| * <td headers="matches classes negation">Any character except {@code a}, {@code b}, or {@code c} (negation)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="range">{@code [a-zA-Z]}</th> |
| * <td headers="matches classes range">{@code a} through {@code z} |
| * or {@code A} through {@code Z}, inclusive (range)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="union">{@code [a-d[m-p]]}</th> |
| * <td headers="matches classes union">{@code a} through {@code d}, |
| * or {@code m} through {@code p}: {@code [a-dm-p]} (union)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="intersection">{@code [a-z&&[def]]}</th> |
| * <td headers="matches classes intersection">{@code d}, {@code e}, or {@code f} (intersection)</tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="subtraction1">{@code [a-z&&[^bc]]}</th> |
| * <td headers="matches classes subtraction1">{@code a} through {@code z}, |
| * except for {@code b} and {@code c}: {@code [ad-z]} (subtraction)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="subtraction2">{@code [a-z&&[^m-p]]}</th> |
| * <td headers="matches classes subtraction2">{@code a} through {@code z}, |
| * and not {@code m} through {@code p}: {@code [a-lq-z]}(subtraction)</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="predef">Predefined character classes</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="any">{@code .}</th> |
| * <td headers="matches predef any">Any character (may or may not match <a href="#lt">line terminators</a>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="digit">{@code \d}</th> |
| * <td headers="matches predef digit">A digit: {@code \p{IsDigit}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_digit">{@code \D}</th> |
| * <td headers="matches predef non_digit">A non-digit: {@code [^\d]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="horiz_white">{@code \h}</th> |
| * <td headers="matches predef horiz_white">A horizontal whitespace character: |
| * <code>[ \t\xA0\u1680\u180e\u2000-\u200a\u202f\u205f\u3000]</code></td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_horiz_white">{@code \H}</th> |
| * <td headers="matches predef non_horiz_white">A non-horizontal whitespace character: {@code [^\h]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="white">{@code \s}</th> |
| * <td headers="matches predef white">A whitespace character: {@code \p{IsWhite_Space}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_white">{@code \S}</th> |
| * <td headers="matches predef non_white">A non-whitespace character: {@code [^\s]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="vert_white">{@code \v}</th> |
| * <td headers="matches predef vert_white">A vertical whitespace character: <code>[\n\x0B\f\r\x85\u2028\u2029]</code> |
| * </td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_vert_white">{@code \V}</th> |
| * <td headers="matches predef non_vert_white">A non-vertical whitespace character: {@code [^\v]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="word">{@code \w}</th> |
| * <td headers="matches predef word">A word character: {@code [\p{alpha}\p{gc=Mark}\p{digit}\p{gc=Connector_Punctuation}\p{Join_Control}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_word">{@code \W}</th> |
| * <td headers="matches predef non_word">A non-word character: {@code [^\w]}</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="posix"><b>POSIX character classes (Unicode-aware)</b></th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Lower">{@code \p{Lower}}</th> |
| * <td headers="matches posix Lower">A lower-case alphabetic character: {@code \p{IsLowercase}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Upper">{@code \p{Upper}}</th> |
| * <td headers="matches posix Upper">An upper-case alphabetic character:{@code \p{IsUppercase}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="ASCII">{@code \p{ASCII}}</th> |
| * <td headers="matches posix ASCII">All ASCII:{@code [\x00-\x7F]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Alpha">{@code \p{Alpha}}</th> |
| * <td headers="matches posix Alpha">An alphabetic character:{@code [\p{IsAlphabetic}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Digit">{@code \p{IsDigit}}</th> |
| * <td headers="matches posix Digit">A decimal digit: {@code \p{gc=Decimal_Number}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Alnum">{@code \p{Alnum}}</th> |
| * <td headers="matches posix Alnum">An alphanumeric character:{@code [\p{Alpha}\p{Digit}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Punct">{@code \p{Punct}}</th> |
| * <td headers="matches posix Punct">Punctuation: {@code \p{IsPunctuation}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Graph">{@code \p{Graph}}</th> |
| * <td headers="matches posix Graph">A visible character: |
| * {@code [^p{space}\p{gc=Control}\p{gc=Surrogate}\p{gc=Unassigned}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Print">{@code \p{Print}}</th> |
| * <td headers="matches posix Print">A printable character: {@code [\p{Graph}\p{Blank}&&[^\p{Cntrl}]]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Blank">{@code \p{Blank}}</th> |
| * <td headers="matches posix Blank">A space or a tab: {@code [\p{gc=Space_Separator}\N{CHARACTER TABULATION}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Cntrl">{@code \p{Cntrl}}</th> |
| * <td headers="matches posix Cntrl">A control character: {@code \p{gc=Control}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="XDigit">{@code \p{XDigit}}</th> |
| * <td headers="matches posix XDigit">A hexadecimal digit: {@code [\p{gc=Decimal_Number}\p{IsHex_Digit}]}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Space">{@code \p{Space}}</th> |
| * <td headers="matches posix Space">A whitespace character: {@code \p{IsWhite_Space}}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="PosixCompatible">POSIX-Compatible expression</th> |
| * <td headers="matches posix PosixCompatible">See <a href="http://www.unicode.org/reports/tr18/#Compatibility_Properties">Unicode documentation</a></td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="java">java.lang.Character classes (simple <a href="#jcc">java character type</a>)</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="javaLowerCase">{@code \p{javaLowerCase}}</th> |
| * <td headers="matches java javaLowerCase">Equivalent to java.lang.Character.isLowerCase()</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="javaUpperCase">{@code \p{javaUpperCase}}</th> |
| * <td headers="matches java javaUpperCase">Equivalent to java.lang.Character.isUpperCase()</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="javaWhitespace">{@code \p{javaWhitespace}}</th> |
| * <td headers="matches java javaWhitespace">Equivalent to java.lang.Character.isWhitespace()</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="javaMirrored">{@code \p{javaMirrored}}</th> |
| * <td headers="matches java javaMirrored">Equivalent to java.lang.Character.isMirrored()</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="unicode">Classes for Unicode scripts, blocks, categories and binary properties</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="IsLatin">{@code \p{IsLatin}}</th> |
| * <td headers="matches unicode IsLatin">A Latin script character (<a href="#usc">script</a>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="InGreek">{@code \p{InGreek}}</th> |
| * <td headers="matches unicode InGreek">A character in the Greek block (<a href="#ubc">block</a>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Lu">{@code \p{Lu}}</th> |
| * <td headers="matches unicode Lu">An uppercase letter (<a href="#ucc">category</a>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="IsAlphabetic">{@code \p{IsAlphabetic}}</th> |
| * <td headers="matches unicode IsAlphabetic">An alphabetic character (<a href="#ubpc">binary property</a>)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="Sc">{@code \p{Sc}}</th> |
| * <td headers="matches unicode Sc">A currency symbol</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="not_InGreek">{@code \P{InGreek}}</th> |
| * <td headers="matches unicode not_InGreek">Any character except one in the Greek block (negation)</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="not_uppercase">{@code [\p{L}&&[^\p{Lu}]]}</th> |
| * <td headers="matches unicode not_uppercase">Any letter except an uppercase letter (subtraction)</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="bounds">Boundary matchers</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="begin_line">{@code ^}</th> |
| * <td headers="matches bounds begin_line">The beginning of a line</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="end_line">{@code $}</th> |
| * <td headers="matches bounds end_line">The end of a line</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="word_boundary">{@code \b}</th> |
| * <td headers="matches bounds word_boundary">A word boundary</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_word_boundary">{@code \B}</th> |
| * <td headers="matches bounds non_word_boundary">A non-word boundary</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="begin_input">{@code \A}</th> |
| * <td headers="matches bounds begin_input">The beginning of the input</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="end_prev_match">{@code \G}</th> |
| * <td headers="matches bounds end_prev_match">The end of the previous match</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="end_input_except_term">{@code \Z}</th> |
| * <td headers="matches bounds end_input_except_term">The end of the input but for the final |
| * <a href="#lt">terminator</a>, if any</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="end_input">{@code \z}</th> |
| * <td headers="matches bounds end_input">The end of the input</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="linebreak">Linebreak matcher</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="any_unicode_linebreak">{@code \R}</th> |
| * <td headers="matches linebreak any_unicode_linebreak">Any Unicode linebreak sequence, is equivalent to |
| * <code>\u000D\u000A|[\u000A\u000B\u000C\u000D\u0085\u2028\u2029] |
| * </code></td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="grapheme">Unicode Extended Grapheme matcher</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="grapheme_any">{@code \X}</th> |
| * <td headers="matches grapheme grapheme_any">Any Unicode extended grapheme cluster</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="greedy">Greedy quantifiers</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_once_or_not"><i>X</i>{@code ?}</th> |
| * <td headers="matches greedy greedy_once_or_not"><i>X</i>, once or not at all</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_zero_or_more"><i>X</i>{@code *}</th> |
| * <td headers="matches greedy greedy_zero_or_more"><i>X</i>, zero or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_one_or_more"><i>X</i>{@code +}</th> |
| * <td headers="matches greedy greedy_one_or_more"><i>X</i>, one or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_exactly"><i>X</i><code>{</code><i>n</i><code>}</code></th> |
| * <td headers="matches greedy greedy_exactly"><i>X</i>, exactly <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_at_least"><i>X</i><code>{</code><i>n</i>{@code ,}}</th> |
| * <td headers="matches greedy greedy_at_least"><i>X</i>, at least <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="greedy_at_least_up_to"><i>X</i><code>{</code><i>n</i>{@code ,}<i>m</i><code>}</code></th> |
| * <td headers="matches greedy greedy_at_least_up_to"><i>X</i>, at least <i>n</i> but not more than <i>m</i> times</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="reluc">Reluctant quantifiers</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_once_or_not"><i>X</i>{@code ??}</th> |
| * <td headers="matches reluc reluc_once_or_not"><i>X</i>, once or not at all</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_zero_or_more"><i>X</i>{@code *?}</th> |
| * <td headers="matches reluc reluc_zero_or_more"><i>X</i>, zero or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_one_or_more"><i>X</i>{@code +?}</th> |
| * <td headers="matches reluc reluc_one_or_more"><i>X</i>, one or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_exactly"><i>X</i><code>{</code><i>n</i><code>}?</code></th> |
| * <td headers="matches reluc reluc_exactly"><i>X</i>, exactly <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_at_least"><i>X</i><code>{</code><i>n</i><code>,}?</code></th> |
| * <td headers="matches reluc reluc_at_least"><i>X</i>, at least <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="reluc_at_least_up_to"><i>X</i><code>{</code><i>n</i>{@code ,}<i>m</i><code>}?</code></th> |
| * <td headers="matches reluc reluc_at_least_up_to"><i>X</i>, at least <i>n</i> but not more than <i>m</i> times</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="poss">Possessive quantifiers</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_once_or_not"><i>X</i>{@code ?+}</th> |
| * <td headers="matches poss poss_once_or_not"><i>X</i>, once or not at all</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_zero_or_more"><i>X</i>{@code *+}</th> |
| * <td headers="matches poss poss_zero_or_more"><i>X</i>, zero or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_one_or_more"><i>X</i>{@code ++}</th> |
| * <td headers="matches poss poss_one_or_more"><i>X</i>, one or more times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_exactly"><i>X</i><code>{</code><i>n</i><code>}+</code></th> |
| * <td headers="matches poss poss_exactly"><i>X</i>, exactly <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_at_least"><i>X</i><code>{</code><i>n</i><code>,}+</code></th> |
| * <td headers="matches poss poss_at_least"><i>X</i>, at least <i>n</i> times</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="poss_at_least_up_to"><i>X</i><code>{</code><i>n</i>{@code ,}<i>m</i><code>}+</code></th> |
| * <td headers="matches poss poss_at_least_up_to"><i>X</i>, at least <i>n</i> but not more than <i>m</i> times</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="logical">Logical operators</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="concat"><i>XY</i></th> |
| * <td headers="matches logical concat"><i>X</i> followed by <i>Y</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="alternate"><i>X</i>{@code |}<i>Y</i></th> |
| * <td headers="matches logical alternate">Either <i>X</i> or <i>Y</i></td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="group">{@code (}<i>X</i>{@code )}</th> |
| * <td headers="matches logical group">X, as a <a href="#cg">capturing group</a></td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="backref">Back references</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="back_nth">{@code \}<i>n</i></th> |
| * <td headers="matches backref back_nth">Whatever the <i>n</i><sup>th</sup> |
| * <a href="#cg">capturing group</a> matched</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="back_named">{@code \}<i>k</i><<i>name</i>></th> |
| * <td headers="matches backref back_named">Whatever the |
| * <a href="#groupname">named-capturing group</a> "name" matched. Only available for API 26 or above</td></tr> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="quote">Quotation</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="quote_follow">{@code \}</th> |
| * <td headers="matches quote quote_follow">Nothing, but quotes the following character</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="quote_begin">{@code \Q}</th> |
| * <td headers="matches quote quote_begin">Nothing, but quotes all characters until {@code \E}</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="quote_end">{@code \E}</th> |
| * <td headers="matches quote quote_end">Nothing, but ends quoting started by {@code \Q}</td></tr> |
| * <!-- Metachars: !$()*+.<>?[\]^{|} --> |
| * |
| * <tr><th colspan="2" style="padding-top:20px" id="special">Special constructs (named-capturing and non-capturing)</th></tr> |
| * |
| * <tr><th style="vertical-align:top; font-weight:normal" id="named_group"><code>(?<<a href="#groupname">name</a>></code><i>X</i>{@code )}</th> |
| * <td headers="matches special named_group"><i>X</i>, as a named-capturing group. Only available for API 26 or above.</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_capture_group">{@code (?:}<i>X</i>{@code )}</th> |
| * <td headers="matches special non_capture_group"><i>X</i>, as a non-capturing group</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="flags"><code>(?idmsux-idmsux) </code></th> |
| * <a href="#UNIX_LINES">d</a> <a href="#MULTILINE">m</a> <a href="#DOTALL">s</a> |
| * <a href="#UNICODE_CASE">u</a> <a href="#COMMENTS">x</a> <a href="#UNICODE_CHARACTER_CLASS">U</a> |
| * on - off</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="non_capture_group_flags">{@code (?idmsuxU-idmsuxU:}<i>X</i>{@code )} </th> |
| * <td headers="matches special non_capture_group_flags"><i>X</i>, as a <a href="#cg">non-capturing group</a> with the |
| * given flags <a href="#CASE_INSENSITIVE">i</a> <a href="#UNIX_LINES">d</a> |
| * <a href="#MULTILINE">m</a> <a href="#DOTALL">s</a> <a href="#UNICODE_CASE">u</a > |
| * <a href="#COMMENTS">x</a> <a href="#UNICODE_CHARACTER_CLASS">U</a> on - off</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="pos_lookahead">{@code (?=}<i>X</i>{@code )}</th> |
| * <td headers="matches special pos_lookahead"><i>X</i>, via zero-width positive lookahead</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="neg_lookahead">{@code (?!}<i>X</i>{@code )}</th> |
| * <td headers="matches special neg_lookahead"><i>X</i>, via zero-width negative lookahead</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="pos_lookbehind">{@code (?<=}<i>X</i>{@code )}</th> |
| * <td headers="matches special pos_lookbehind"><i>X</i>, via zero-width positive lookbehind</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="neg_lookbehind">{@code (?<!}<i>X</i>{@code )}</th> |
| * <td headers="matches special neg_lookbehind"><i>X</i>, via zero-width negative lookbehind</td></tr> |
| * <tr><th style="vertical-align:top; font-weight:normal" id="indep_non_capture_group">{@code (?>}<i>X</i>{@code )}</th> |
| * <td headers="matches special indep_non_capture_group"><i>X</i>, as an independent, non-capturing group</td></tr> |
| * |
| * </tbody> |
| * </table> |
| * |
| * <hr> |
| * |
| * |
| * <h2><a id="bs">Backslashes, escapes, and quoting</a></h2> |
| * |
| * <p> The backslash character ({@code '\'}) serves to introduce escaped |
| * constructs, as defined in the table above, as well as to quote characters |
| * that otherwise would be interpreted as unescaped constructs. Thus the |
| * expression {@code \\} matches a single backslash and <code>\{</code> matches a |
| * left brace. |
| * |
| * <p> It is an error to use a backslash prior to any alphabetic character that |
| * does not denote an escaped construct; these are reserved for future |
| * extensions to the regular-expression language. A backslash may be used |
| * prior to a non-alphabetic character regardless of whether that character is |
| * part of an unescaped construct. |
| * |
| * <p> Backslashes within string literals in Java source code are interpreted |
| * as required by |
| * <cite>The Java Language Specification</cite> |
| * as either Unicode escapes (section {@jls 3.3}) or other character escapes (section {@jls 3.10.6}) |
| * It is therefore necessary to double backslashes in string |
| * literals that represent regular expressions to protect them from |
| * interpretation by the Java bytecode compiler. The string literal |
| * <code>"\b"</code>, for example, matches a single backspace character when |
| * interpreted as a regular expression, while {@code "\\b"} matches a |
| * word boundary. The string literal {@code "\(hello\)"} is illegal |
| * and leads to a compile-time error; in order to match the string |
| * {@code (hello)} the string literal {@code "\\(hello\\)"} |
| * must be used. |
| * |
| * <h2><a id="cc">Character Classes</a></h2> |
| * |
| * <p> Character classes may appear within other character classes, and |
| * may be composed by the union operator (implicit) and the intersection |
| * operator ({@code &&}). |
| * The union operator denotes a class that contains every character that is |
| * in at least one of its operand classes. The intersection operator |
| * denotes a class that contains every character that is in both of its |
| * operand classes. |
| * |
| * <p> The precedence of character-class operators is as follows, from |
| * highest to lowest: |
| * |
| * <table class="striped" style="margin-left: 2em;"> |
| * <caption style="display:none">Precedence of character class operators.</caption> |
| * <thead> |
| * <tr><th scope="col">Precedence<th scope="col">Name<th scope="col">Example |
| * </thead> |
| * <tbody> |
| * <tr><th scope="row">1</th> |
| * <td>Literal escape </td> |
| * <td>{@code \x}</td></tr> |
| * <tr><th scope="row">2</th> |
| * <td>Grouping</td> |
| * <td>{@code [...]}</td></tr> |
| * <tr><th scope="row">3</th> |
| * <td>Range</td> |
| * <td>{@code a-z}</td></tr> |
| * <tr><th scope="row">4</th> |
| * <td>Union</td> |
| * <td>{@code [a-e][i-u]}</td></tr> |
| * <tr><th scope="row">5</th> |
| * <td>Intersection</td> |
| * <td>{@code [a-z&&[aeiou]]}</td></tr> |
| * </tbody> |
| * </table> |
| * |
| * <p> Note that a different set of metacharacters are in effect inside |
| * a character class than outside a character class. For instance, the |
| * regular expression {@code .} loses its special meaning inside a |
| * character class, while the expression {@code -} becomes a range |
| * forming metacharacter. |
| * |
| * <h2><a id="lt">Line terminators</a></h2> |
| * |
| * <p> A <i>line terminator</i> is a one- or two-character sequence that marks |
| * the end of a line of the input character sequence. The following are |
| * recognized as line terminators: |
| * |
| * <ul> |
| * |
| * <li> A newline (line feed) character ({@code '\n'}), |
| * |
| * <li> A carriage-return character followed immediately by a newline |
| * character ({@code "\r\n"}), |
| * |
| * <li> A standalone carriage-return character ({@code '\r'}), |
| * |
| * <li> A next-line character (<code>'\u0085'</code>), |
| * |
| * <li> A line-separator character (<code>'\u2028'</code>), or |
| * |
| * <li> A paragraph-separator character (<code>'\u2029'</code>). |
| * |
| * </ul> |
| * <p>If {@link #UNIX_LINES} mode is activated, then the only line terminators |
| * recognized are newline characters. |
| * |
| * <p> The regular expression {@code .} matches any character except a line |
| * terminator unless the {@link #DOTALL} flag is specified. |
| * |
| * <p> By default, the regular expressions {@code ^} and {@code $} ignore |
| * line terminators and only match at the beginning and the end, respectively, |
| * of the entire input sequence. If {@link #MULTILINE} mode is activated then |
| * {@code ^} matches at the beginning of input and after any line terminator |
| * except at the end of input. When in {@link #MULTILINE} mode {@code $} |
| * matches just before a line terminator or the end of the input sequence. |
| * |
| * <h2><a id="cg">Groups and capturing</a></h2> |
| * |
| * <h3><a id="gnumber">Group number</a></h3> |
| * <p> Capturing groups are numbered by counting their opening parentheses from |
| * left to right. In the expression {@code ((A)(B(C)))}, for example, there |
| * are four such groups: </p> |
| * |
| * <ol style="margin-left:2em;"> |
| * <li> {@code ((A)(B(C)))} |
| * <li> {@code (A)} |
| * <li> {@code (B(C))} |
| * <li> {@code (C)} |
| * </ol> |
| * |
| * <p> Group zero always stands for the entire expression. |
| * |
| * <p> Capturing groups are so named because, during a match, each subsequence |
| * of the input sequence that matches such a group is saved. The captured |
| * subsequence may be used later in the expression, via a back reference, and |
| * may also be retrieved from the matcher once the match operation is complete. |
| * |
| * <h3><a id="groupname">Group name</a></h3> |
| * <p>The constructs and APIs are available since API level 26. A capturing group |
| * can also be assigned a "name", a {@code named-capturing group}, |
| * and then be back-referenced later by the "name". Group names are composed of |
| * the following characters. The first character must be a {@code letter}. |
| * |
| * <ul> |
| * <li> The uppercase letters {@code 'A'} through {@code 'Z'} |
| * (<code>'\u0041'</code> through <code>'\u005a'</code>), |
| * <li> The lowercase letters {@code 'a'} through {@code 'z'} |
| * (<code>'\u0061'</code> through <code>'\u007a'</code>), |
| * <li> The digits {@code '0'} through {@code '9'} |
| * (<code>'\u0030'</code> through <code>'\u0039'</code>), |
| * </ul> |
| * |
| * <p> A {@code named-capturing group} is still numbered as described in |
| * <a href="#gnumber">Group number</a>. |
| * |
| * <p> The captured input associated with a group is always the subsequence |
| * that the group most recently matched. If a group is evaluated a second time |
| * because of quantification then its previously-captured value, if any, will |
| * be retained if the second evaluation fails. Matching the string |
| * {@code "aba"} against the expression {@code (a(b)?)+}, for example, leaves |
| * group two set to {@code "b"}. All captured input is discarded at the |
| * beginning of each match. |
| * |
| * <p> Groups beginning with {@code (?} are either pure, <i>non-capturing</i> groups |
| * that do not capture text and do not count towards the group total, or |
| * <i>named-capturing</i> group. |
| * |
| * <h2> Unicode support </h2> |
| * |
| * <p> This class is in conformance with Level 1 of <a |
| * href="http://www.unicode.org/reports/tr18/"><i>Unicode Technical |
| * Standard #18: Unicode Regular Expressions</i></a>, plus RL2.1 |
| * Canonical Equivalents and RL2.2 Extended Grapheme Clusters. |
| * <p> |
| * <b>Unicode escape sequences</b> such as <code>\u2014</code> in Java source code |
| * are processed as described in section {@jls 3.3} of |
| * <cite>The Java Language Specification</cite>. |
| * Such escape sequences are also implemented directly by the regular-expression |
| * parser so that Unicode escapes can be used in expressions that are read from |
| * files or from the keyboard. Thus the strings <code>"\u2014"</code> and |
| * {@code "\\u2014"}, while not equal, compile into the same pattern, which |
| * matches the character with hexadecimal value {@code 0x2014}. |
| * <p> |
| * A Unicode character can also be represented by using its <b>Hex notation</b> |
| * (hexadecimal code point value) directly as described in construct |
| * <code>\x{...}</code>, for example a supplementary character U+2011F can be |
| * specified as <code>\x{2011F}</code>, instead of two consecutive Unicode escape |
| * sequences of the surrogate pair <code>\uD840</code><code>\uDD1F</code>. |
| * <p> |
| * <b>Unicode character names</b> are supported by the named character construct |
| * <code>\N{</code>...<code>}</code>, for example, <code>\N{WHITE SMILING FACE}</code> |
| * specifies character <code>\u263A</code>. The character names supported |
| * by this class are the valid Unicode character names matched by |
| * {@code java.lang.Character.codePointOf(String) Character.codePointOf(name)}. |
| * <p> |
| * <a href="http://www.unicode.org/reports/tr18/#Default_Grapheme_Clusters"> |
| * <b>Unicode extended grapheme clusters</b></a> are supported by the grapheme |
| * cluster matcher {@code \X}. |
| * <p> |
| * Unicode scripts, blocks, categories and binary properties are written with |
| * the {@code \p} and {@code \P} constructs as in Perl. |
| * <code>\p{</code><i>prop</i><code>}</code> matches if |
| * the input has the property <i>prop</i>, while <code>\P{</code><i>prop</i><code>}</code> |
| * does not match if the input has that property. |
| * <p> |
| * Scripts, blocks, categories and binary properties can be used both inside |
| * and outside of a character class. |
| * |
| * <p> |
| * <b><a id="usc">Scripts</a></b> are specified either with the prefix {@code Is} supported since |
| * Android 10, as in {@code IsHiragana}, or by using the {@code script} keyword (or its short |
| * form {@code sc}) as in {@code script=Hiragana} or {@code sc=Hiragana}. |
| * <p> |
| * The script names supported by {@code Pattern} are the valid script names |
| * accepted and defined by |
| * {@link java.lang.Character.UnicodeScript#forName(String) UnicodeScript.forName}. |
| * |
| * <p> |
| * <b><a id="ubc">Blocks</a></b> are specified with the prefix {@code In}, as in |
| * {@code InMongolian}, or by using the keyword {@code block} (or its short |
| * form {@code blk}) as in {@code block=Mongolian} or {@code blk=Mongolian}. |
| * <p> |
| * The block names supported by {@code Pattern} are the valid block names |
| * accepted and defined by |
| * {@link java.lang.Character.UnicodeBlock#forName(String) UnicodeBlock.forName}. |
| * <p> |
| * |
| * <b><a id="ucc">Categories</a></b> may be specified with the optional prefix {@code Is}: |
| * Both {@code \p{IsL}} supported since Android 10 and {@code \p{L}} denote the category of Unicode |
| * letters. Same as scripts and blocks, categories can also be specified |
| * by using the keyword {@code general_category} (or its short form |
| * {@code gc}) as in {@code general_category=Lu} or {@code gc=Lu}. |
| * <p> |
| * The supported categories are those of |
| * <a href="http://www.unicode.org/standard/standard.html"> |
| * <i>The Unicode Standard</i></a> in the version specified by the |
| * {@link java.lang.Character Character} class. The category names are those |
| * defined in the Standard, both normative and informative. |
| * <p> |
| * |
| * <b><a id="ubpc">Binary properties</a></b> are specified with the prefix {@code Is} since |
| * Android 10, as in {@code IsAlphabetic}. The prefix {@code Is} isn't needed before Android 10, |
| * as in {@code Alphabetic}. The supported binary properties by {@code Pattern} |
| * are |
| * <ul> |
| * <li> Alphabetic |
| * <li> Ideographic |
| * <li> Letter |
| * <li> Lowercase |
| * <li> Uppercase |
| * <li> Titlecase |
| * <li> Punctuation |
| * <Li> Control |
| * <li> White_Space |
| * <li> Digit |
| * <li> Hex_Digit |
| * <li> Join_Control |
| * <li> Noncharacter_Code_Point |
| * <li> Assigned |
| * </ul> |
| * <p> |
| * The <b>Predefined Character classes</b> and <b>POSIX character classes</b> |
| * are in conformance with the recommendation of <i>Annex C: Compatibility Properties</i> |
| * of <a href="http://www.unicode.org/reports/tr18/"><i>Unicode Technical Standard #18: |
| * Unicode Regular Expressions</i></a>. |
| * |
| * <p> |
| * <a id="jcc"> |
| * Categories that behave like the java.lang.Character |
| * boolean is<i>methodname</i> methods (except for the deprecated ones) are |
| * available through the same <code>\p{</code><i>prop</i><code>}</code> syntax where |
| * the specified property has the name <code>java<i>methodname</i></code></a>. |
| * |
| * <h3> Behavior starting from API level 10 (Android 2.3) </h3> |
| * |
| * <p> Starting from Android 2.3 Gingerbread, ICU4C becomes the backend of the regular expression |
| * implementation. Android could behave differently compared with other regex implementation, e.g. |
| * literal right brace ('}') has to be escaped on Android.</p> |
| * |
| * <p> Some other behavior differences can be found in the |
| * <a href="https://unicode-org.github.io/icu/userguide/strings/regexp.html#differences-with-java-regular-expressions"> |
| * ICU documentation</a>. </p> |
| * |
| * <h2> Comparison to Perl 5 </h2> |
| * |
| * <p>The {@code Pattern} engine performs traditional NFA-based matching |
| * with ordered alternation as occurs in Perl 5. |
| * |
| * <p> Perl constructs not supported by this class: </p> |
| * |
| * <ul> |
| * <li><p> The backreference constructs, <code>\g{</code><i>n</i><code>}</code> for |
| * the <i>n</i><sup>th</sup><a href="#cg">capturing group</a> and |
| * <code>\g{</code><i>name</i><code>}</code> for |
| * <a href="#groupname">named-capturing group</a>. |
| * </p></li> |
| * |
| * <li><p> The conditional constructs |
| * {@code (?(}<i>condition</i>{@code )}<i>X</i>{@code )} and |
| * {@code (?(}<i>condition</i>{@code )}<i>X</i>{@code |}<i>Y</i>{@code )}, |
| * </p></li> |
| * |
| * <li><p> The embedded code constructs <code>(?{</code><i>code</i><code>})</code> |
| * and <code>(??{</code><i>code</i><code>})</code>,</p></li> |
| * |
| * <li><p> The embedded comment syntax {@code (?#comment)}, and </p></li> |
| * |
| * <li><p> The preprocessing operations {@code \l} <code>\u</code>, |
| * {@code \L}, and {@code \U}. </p></li> |
| * |
| * </ul> |
| * |
| * <p> Constructs supported by this class but not by Perl: </p> |
| * |
| * <ul> |
| * |
| * <li><p> Character-class union and intersection as described |
| * <a href="#cc">above</a>.</p></li> |
| * |
| * </ul> |
| * |
| * <p> Notable differences from Perl: </p> |
| * |
| * <ul> |
| * |
| * <li><p> In Perl, {@code \1} through {@code \9} are always interpreted |
| * as back references; a backslash-escaped number greater than {@code 9} is |
| * treated as a back reference if at least that many subexpressions exist, |
| * otherwise it is interpreted, if possible, as an octal escape. In this |
| * class octal escapes must always begin with a zero. In this class, |
| * {@link #compile(String)} throws {@link PatternSyntaxException} for any |
| * non-existent back references. Please use {@code \Q} and {@code \E} to |
| * quote any digit literals followed by back references. |
| * </p></li> |
| * |
| * <li><p> Perl uses the {@code g} flag to request a match that resumes |
| * where the last match left off. This functionality is provided implicitly |
| * by the {@link Matcher} class: Repeated invocations of the {@link |
| * Matcher#find find} method will resume where the last match left off, |
| * unless the matcher is reset. </p></li> |
| * |
| * <li><p> In Perl, embedded flags at the top level of an expression affect |
| * the whole expression. In this class, embedded flags always take effect |
| * at the point at which they appear, whether they are at the top level or |
| * within a group; in the latter case, flags are restored at the end of the |
| * group just as in Perl. </p></li> |
| * |
| * </ul> |
| * |
| * |
| * <p> For a more precise description of the behavior of regular expression |
| * constructs, please see <a href="http://www.oreilly.com/catalog/regex3/"> |
| * <i>Mastering Regular Expressions, 3rd Edition</i>, Jeffrey E. F. Friedl, |
| * O'Reilly and Associates, 2006.</a> |
| * </p> |
| * |
| * @see java.lang.String#split(String, int) |
| * @see java.lang.String#split(String) |
| * |
| * @author Mike McCloskey |
| * @author Mark Reinhold |
| * @author JSR-51 Expert Group |
| * @since 1.4 |
| */ |
| |
| public final class Pattern |
| implements java.io.Serializable |
| { |
| |
| /* |
| * Regular expression modifier values. Instead of being passed as |
| * arguments, they can also be passed as inline modifiers. |
| * For example, the following statements have the same effect. |
| * |
| * Pattern p1 = Pattern.compile("abc", Pattern.CASE_INSENSITIVE|Pattern.MULTILINE); |
| * Pattern p2 = Pattern.compile("(?im)abc", 0); |
| */ |
| |
| /** |
| * Enables Unix lines mode. |
| * |
| * <p> In this mode, only the {@code '\n'} line terminator is recognized |
| * in the behavior of {@code .}, {@code ^}, and {@code $}. |
| * |
| * <p> Unix lines mode can also be enabled via the embedded flag |
| * expression {@code (?d)}. |
| */ |
| public static final int UNIX_LINES = 0x01; |
| |
| // Android-changed: CASE_INSENSITIVE is Unicode-aware on Android. |
| /** |
| * Enables case-insensitive matching. |
| * |
| * <p> Case-insensitive matching is Unicode-aware on Android. |
| * |
| * <p> Case-insensitive matching can also be enabled via the embedded flag |
| * expression {@code (?i)}. |
| * |
| * <p> Specifying this flag may impose a slight performance penalty. </p> |
| */ |
| public static final int CASE_INSENSITIVE = 0x02; |
| |
| /** |
| * Permits whitespace and comments in pattern. |
| * |
| * <p> In this mode, whitespace is ignored, and embedded comments starting |
| * with {@code #} are ignored until the end of a line. |
| * |
| * <p> Comments mode can also be enabled via the embedded flag |
| * expression {@code (?x)}. |
| */ |
| public static final int COMMENTS = 0x04; |
| |
| /** |
| * Enables multiline mode. |
| * |
| * <p> In multiline mode the expressions {@code ^} and {@code $} match |
| * just after or just before, respectively, a line terminator or the end of |
| * the input sequence. By default these expressions only match at the |
| * beginning and the end of the entire input sequence. |
| * |
| * <p> Multiline mode can also be enabled via the embedded flag |
| * expression {@code (?m)}. </p> |
| */ |
| public static final int MULTILINE = 0x08; |
| |
| /** |
| * Enables literal parsing of the pattern. |
| * |
| * <p> When this flag is specified then the input string that specifies |
| * the pattern is treated as a sequence of literal characters. |
| * Metacharacters or escape sequences in the input sequence will be |
| * given no special meaning. |
| * |
| * <p>The flags CASE_INSENSITIVE and UNICODE_CASE retain their impact on |
| * matching when used in conjunction with this flag. The other flags |
| * become superfluous. |
| * |
| * <p> There is no embedded flag character for enabling literal parsing. |
| * @since 1.5 |
| */ |
| public static final int LITERAL = 0x10; |
| |
| /** |
| * Enables dotall mode. |
| * |
| * <p> In dotall mode, the expression {@code .} matches any character, |
| * including a line terminator. By default this expression does not match |
| * line terminators. |
| * |
| * <p> Dotall mode can also be enabled via the embedded flag |
| * expression {@code (?s)}. (The {@code s} is a mnemonic for |
| * "single-line" mode, which is what this is called in Perl.) </p> |
| */ |
| public static final int DOTALL = 0x20; |
| |
| // Android-changed: UNICODE_CASE flag is ignored. |
| /** |
| * Enables Unicode-aware case folding. This flag is ignoredon Android. |
| * When {@link #CASE_INSENSITIVE} flag is provided, case-insensitive |
| * matching is always done in a manner consistent with the Unicode Standard. |
| * |
| * <p> The embedded flag {@code (?u)} is ignored. |
| * |
| * <p> Specifying this flag may impose a performance penalty. </p> |
| */ |
| public static final int UNICODE_CASE = 0x40; |
| |
| // Android-changed: Android does not support CANON_EQ flag. |
| /** |
| * This flag is not supported on Android. |
| */ |
| public static final int CANON_EQ = 0x80; |
| |
| // Android-changed: Android always uses unicode character classes. |
| /** |
| * This flag is not supported on Android, and Unicode character classes are always |
| * used. |
| * <p> |
| * See the Unicode version of |
| * <i>Predefined character classes</i> and <i>POSIX character classes</i> |
| * are in conformance with |
| * <a href="http://www.unicode.org/reports/tr18/"><i>Unicode Technical |
| * Standard #18: Unicode Regular Expressions</i></a> |
| * <i>Annex C: Compatibility Properties</i>. |
| * <p> |
| * @since 1.7 |
| */ |
| public static final int UNICODE_CHARACTER_CLASS = 0x100; |
| |
| /** |
| * Contains all possible flags for compile(regex, flags). |
| */ |
| private static final int ALL_FLAGS = CASE_INSENSITIVE | MULTILINE | |
| // Android-changed: CANON_EQ and UNICODE_CHARACTER_CLASS flags aren't supported. |
| // DOTALL | UNICODE_CASE | CANON_EQ | UNIX_LINES | LITERAL | |
| // UNICODE_CHARACTER_CLASS | COMMENTS; |
| DOTALL | UNICODE_CASE | UNIX_LINES | LITERAL | COMMENTS; |
| |
| /* Pattern has only two serialized components: The pattern string |
| * and the flags, which are all that is needed to recompile the pattern |
| * when it is deserialized. |
| */ |
| |
| /** use serialVersionUID from Merlin b59 for interoperability */ |
| @java.io.Serial |
| private static final long serialVersionUID = 5073258162644648461L; |
| |
| /** |
| * The original regular-expression pattern string. |
| * |
| * @serial |
| */ |
| // Android-changed: reimplement matching logic natively via ICU. |
| // private String pattern; |
| private final String pattern; |
| |
| /** |
| * The original pattern flags. |
| * |
| * @serial |
| */ |
| // Android-changed: reimplement matching logic natively via ICU. |
| // private int flags; |
| private final int flags; |
| |
| |
| // BEGIN Android-changed: reimplement matching logic natively via ICU. |
| // We only need some tie-ins to native memory, instead of a large number |
| // of fields on the .java side. |
| /* package */ transient PatternNative nativePattern; |
| // END Android-changed: reimplement matching logic natively via ICU. |
| |
| /** |
| * Compiles the given regular expression into a pattern. |
| * |
| * @param regex |
| * The expression to be compiled |
| * @return the given regular expression compiled into a pattern |
| * @throws PatternSyntaxException |
| * If the expression's syntax is invalid |
| */ |
| public static Pattern compile(String regex) { |
| return new Pattern(regex, 0); |
| } |
| |
| // Android-changed: Android doesn't support CANON_EQ and UNICODE_CHARACTER_CLASS flags. |
| /** |
| * Compiles the given regular expression into a pattern with the given |
| * flags. |
| * |
| * @param regex |
| * The expression to be compiled |
| * |
| * @param flags |
| * Match flags, a bit mask that may include |
| * {@link #CASE_INSENSITIVE}, {@link #MULTILINE}, {@link #DOTALL}, |
| * {@link #UNICODE_CASE}, {@link #UNIX_LINES}, {@link #LITERAL}, |
| * and {@link #COMMENTS} |
| * |
| * @return the given regular expression compiled into a pattern with the given flags |
| * @throws IllegalArgumentException |
| * If bit values other than those corresponding to the defined |
| * match flags are set in {@code flags} |
| * |
| * @throws PatternSyntaxException |
| * If the expression's syntax is invalid |
| */ |
| public static Pattern compile(String regex, int flags) { |
| return new Pattern(regex, flags); |
| } |
| |
| /** |
| * Returns the regular expression from which this pattern was compiled. |
| * |
| * @return The source of this pattern |
| */ |
| public String pattern() { |
| return pattern; |
| } |
| |
| /** |
| * <p>Returns the string representation of this pattern. This |
| * is the regular expression from which this pattern was |
| * compiled.</p> |
| * |
| * @return The string representation of this pattern |
| * @since 1.5 |
| */ |
| public String toString() { |
| return pattern; |
| } |
| |
| /** |
| * Creates a matcher that will match the given input against this pattern. |
| * |
| * @param input |
| * The character sequence to be matched |
| * |
| * @return A new matcher for this pattern |
| */ |
| public Matcher matcher(CharSequence input) { |
| // Android-removed: Pattern is eagerly compiled() upon construction. |
| /* |
| if (!compiled) { |
| synchronized(this) { |
| if (!compiled) |
| compile(); |
| } |
| } |
| */ |
| Matcher m = new Matcher(this, input); |
| return m; |
| } |
| |
| /** |
| * Returns this pattern's match flags. |
| * |
| * @return The match flags specified when this pattern was compiled |
| */ |
| public int flags() { |
| // Android-changed: We don't need the temporary pattern flags0. |
| // return flags0; |
| return flags; |
| } |
| |
| /** |
| * Compiles the given regular expression and attempts to match the given |
| * input against it. |
| * |
| * <p> An invocation of this convenience method of the form |
| * |
| * <blockquote><pre> |
| * Pattern.matches(regex, input);</pre></blockquote> |
| * |
| * behaves in exactly the same way as the expression |
| * |
| * <blockquote><pre> |
| * Pattern.compile(regex).matcher(input).matches()</pre></blockquote> |
| * |
| * <p> If a pattern is to be used multiple times, compiling it once and reusing |
| * it will be more efficient than invoking this method each time. </p> |
| * |
| * @param regex |
| * The expression to be compiled |
| * |
| * @param input |
| * The character sequence to be matched |
| * @return whether or not the regular expression matches on the input |
| * @throws PatternSyntaxException |
| * If the expression's syntax is invalid |
| */ |
| public static boolean matches(String regex, CharSequence input) { |
| Pattern p = Pattern.compile(regex); |
| Matcher m = p.matcher(input); |
| return m.matches(); |
| } |
| |
| // Android-changed: Adopt split() behavior change only for apps targeting API > 28. |
| // http://b/109659282#comment7 |
| /** |
| * Splits the given input sequence around matches of this pattern. |
| * |
| * <p> The array returned by this method contains each substring of the |
| * input sequence that is terminated by another subsequence that matches |
| * this pattern or is terminated by the end of the input sequence. The |
| * substrings in the array are in the order in which they occur in the |
| * input. If this pattern does not match any subsequence of the input then |
| * the resulting array has just one element, namely the input sequence in |
| * string form. |
| * |
| * <p> When there is a positive-width match at the beginning of the input |
| * sequence then an empty leading substring is included at the beginning |
| * of the resulting array. A zero-width match at the beginning however |
| * can only produce such an empty leading substring for apps running on or |
| * targeting API versions <= 28. |
| * |
| * <p> The {@code limit} parameter controls the number of times the |
| * pattern is applied and therefore affects the length of the resulting |
| * array. |
| * <ul> |
| * <li><p> |
| * If the <i>limit</i> is positive then the pattern will be applied |
| * at most <i>limit</i> - 1 times, the array's length will be |
| * no greater than <i>limit</i>, and the array's last entry will contain |
| * all input beyond the last matched delimiter.</p></li> |
| * |
| * <li><p> |
| * If the <i>limit</i> is zero then the pattern will be applied as |
| * many times as possible, the array can have any length, and trailing |
| * empty strings will be discarded.</p></li> |
| * |
| * <li><p> |
| * If the <i>limit</i> is negative then the pattern will be applied |
| * as many times as possible and the array can have any length.</p></li> |
| * </ul> |
| * |
| * <p> The input {@code "boo:and:foo"}, for example, yields the following |
| * results with these parameters: |
| * |
| * <table class="plain" style="margin-left:2em;"> |
| * <caption style="display:none">Split example showing regex, limit, and result</caption> |
| * <thead> |
| * <tr> |
| * <th scope="col">Regex</th> |
| * <th scope="col">Limit</th> |
| * <th scope="col">Result</th> |
| * </tr> |
| * </thead> |
| * <tbody> |
| * <tr><th scope="row" rowspan="3" style="font-weight:normal">:</th> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">2</th> |
| * <td>{@code { "boo", "and:foo" }}</td></tr> |
| * <tr><!-- : --> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">5</th> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><!-- : --> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">-2</th> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><th scope="row" rowspan="3" style="font-weight:normal">o</th> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">5</th> |
| * <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
| * <tr><!-- o --> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">-2</th> |
| * <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
| * <tr><!-- o --> |
| * <th scope="row" style="font-weight:normal; text-align:right; padding-right:1em">0</th> |
| * <td>{@code { "b", "", ":and:f" }}</td></tr> |
| * </tbody> |
| * </table> |
| * |
| * @param input |
| * The character sequence to be split |
| * |
| * @param limit |
| * The result threshold, as described above |
| * |
| * @return The array of strings computed by splitting the input |
| * around matches of this pattern |
| */ |
| public String[] split(CharSequence input, int limit) { |
| // BEGIN Android-added: fastSplit() to speed up simple cases. |
| String[] fast = fastSplit(pattern, input.toString(), limit); |
| if (fast != null) { |
| return fast; |
| } |
| // END Android-added: fastSplit() to speed up simple cases. |
| int index = 0; |
| boolean matchLimited = limit > 0; |
| ArrayList<String> matchList = new ArrayList<>(); |
| Matcher m = matcher(input); |
| |
| // Add segments before each match found |
| while(m.find()) { |
| if (!matchLimited || matchList.size() < limit - 1) { |
| if (index == 0 && index == m.start() && m.start() == m.end()) { |
| // no empty leading substring included for zero-width match |
| // at the beginning of the input char sequence. |
| // BEGIN Android-changed: split() compat behavior for apps targeting <= 28. |
| // continue; |
| int targetSdkVersion = VMRuntime.getRuntime().getTargetSdkVersion(); |
| if (targetSdkVersion > 28) { |
| continue; |
| } |
| // END Android-changed: split() compat behavior for apps targeting <= 28. |
| } |
| String match = input.subSequence(index, m.start()).toString(); |
| matchList.add(match); |
| index = m.end(); |
| } else if (matchList.size() == limit - 1) { // last one |
| String match = input.subSequence(index, |
| input.length()).toString(); |
| matchList.add(match); |
| index = m.end(); |
| } |
| } |
| |
| // If no match was found, return this |
| if (index == 0) |
| return new String[] {input.toString()}; |
| |
| // Add remaining segment |
| if (!matchLimited || matchList.size() < limit) |
| matchList.add(input.subSequence(index, input.length()).toString()); |
| |
| // Construct result |
| int resultSize = matchList.size(); |
| if (limit == 0) |
| while (resultSize > 0 && matchList.get(resultSize-1).isEmpty()) |
| resultSize--; |
| String[] result = new String[resultSize]; |
| return matchList.subList(0, resultSize).toArray(result); |
| } |
| |
| // BEGIN Android-added: fastSplit() to speed up simple cases. |
| private static final String FASTSPLIT_METACHARACTERS = "\\?*+[](){}^$.|"; |
| |
| /** |
| * Returns a result equivalent to {@code s.split(separator, limit)} if it's able |
| * to compute it more cheaply than native impl, or null if the caller should fall back to |
| * using native impl. |
| * |
| * fastpath will work if the regex is a |
| * (1)one-char String and this character is not one of the |
| * RegEx's meta characters ".$|()[{^?*+\\", or |
| * (2)two-char String and the first char is the backslash and |
| * the second is one of regEx's meta characters ".$|()[{^?*+\\". |
| * @hide |
| */ |
| public static String[] fastSplit(String re, String input, int limit) { |
| // Can we do it cheaply? |
| int len = re.length(); |
| if (len == 0) { |
| return null; |
| } |
| char ch = re.charAt(0); |
| if (len == 1) { |
| if (Character.isSurrogate(ch)) { |
| // Single surrogate is an invalid UTF-16 sequence. |
| return null; |
| } else if (FASTSPLIT_METACHARACTERS.indexOf(ch) != -1) { |
| // We don't allow a single metacharacter. |
| return null; |
| } |
| // pass through |
| } else if (len == 2 && ch == '\\') { |
| // We're looking for a quoted character. |
| // Quoted metacharacters are effectively single non-metacharacters. |
| ch = re.charAt(1); |
| if (FASTSPLIT_METACHARACTERS.indexOf(ch) == -1) { |
| return null; |
| } |
| } else { |
| return null; |
| } |
| |
| // We can do this cheaply... |
| |
| // Unlike Perl, which considers the result of splitting the empty string to be the empty |
| // array, Java returns an array containing the empty string. |
| if (input.isEmpty()) { |
| return new String[] { "" }; |
| } |
| |
| // Count separators |
| int separatorCount = 0; |
| int begin = 0; |
| int end; |
| while (separatorCount + 1 != limit && (end = input.indexOf(ch, begin)) != -1) { |
| ++separatorCount; |
| begin = end + 1; |
| } |
| int lastPartEnd = input.length(); |
| if (limit == 0 && begin == lastPartEnd) { |
| // Last part is empty for limit == 0, remove all trailing empty matches. |
| if (separatorCount == lastPartEnd) { |
| // Input contains only separators. |
| return EmptyArray.STRING; |
| } |
| // Find the beginning of trailing separators. |
| do { |
| --begin; |
| } while (input.charAt(begin - 1) == ch); |
| // Reduce separatorCount and fix lastPartEnd. |
| separatorCount -= input.length() - begin; |
| lastPartEnd = begin; |
| } |
| |
| // Collect the result parts. |
| String[] result = new String[separatorCount + 1]; |
| begin = 0; |
| for (int i = 0; i != separatorCount; ++i) { |
| end = input.indexOf(ch, begin); |
| result[i] = input.substring(begin, end); |
| begin = end + 1; |
| } |
| // Add last part. |
| result[separatorCount] = input.substring(begin, lastPartEnd); |
| return result; |
| } |
| // END Android-added: fastSplit() to speed up simple cases. |
| |
| /** |
| * Splits the given input sequence around matches of this pattern. |
| * |
| * <p> This method works as if by invoking the two-argument {@link |
| * #split(java.lang.CharSequence, int) split} method with the given input |
| * sequence and a limit argument of zero. Trailing empty strings are |
| * therefore not included in the resulting array. </p> |
| * |
| * <p> The input {@code "boo:and:foo"}, for example, yields the following |
| * results with these expressions: |
| * |
| * <table class="plain" style="margin-left:2em"> |
| * <caption style="display:none">Split examples showing regex and result</caption> |
| * <thead> |
| * <tr> |
| * <th scope="col">Regex</th> |
| * <th scope="col">Result</th> |
| * </tr> |
| * </thead> |
| * <tbody> |
| * <tr><th scope="row" style="text-weight:normal">:</th> |
| * <td>{@code { "boo", "and", "foo" }}</td></tr> |
| * <tr><th scope="row" style="text-weight:normal">o</th> |
| * <td>{@code { "b", "", ":and:f" }}</td></tr> |
| * </tbody> |
| * </table> |
| * |
| * |
| * @param input |
| * The character sequence to be split |
| * |
| * @return The array of strings computed by splitting the input |
| * around matches of this pattern |
| */ |
| public String[] split(CharSequence input) { |
| return split(input, 0); |
| } |
| |
| /** |
| * Returns a literal pattern {@code String} for the specified |
| * {@code String}. |
| * |
| * <p>This method produces a {@code String} that can be used to |
| * create a {@code Pattern} that would match the string |
| * {@code s} as if it were a literal pattern.</p> Metacharacters |
| * or escape sequences in the input sequence will be given no special |
| * meaning. |
| * |
| * @param s The string to be literalized |
| * @return A literal string replacement |
| * @since 1.5 |
| */ |
| public static String quote(String s) { |
| int slashEIndex = s.indexOf("\\E"); |
| if (slashEIndex == -1) |
| return "\\Q" + s + "\\E"; |
| |
| int lenHint = s.length(); |
| lenHint = (lenHint < Integer.MAX_VALUE - 8 - lenHint) ? |
| (lenHint << 1) : (Integer.MAX_VALUE - 8); |
| |
| StringBuilder sb = new StringBuilder(lenHint); |
| sb.append("\\Q"); |
| int current = 0; |
| do { |
| sb.append(s, current, slashEIndex) |
| .append("\\E\\\\E\\Q"); |
| current = slashEIndex + 2; |
| } while ((slashEIndex = s.indexOf("\\E", current)) != -1); |
| |
| return sb.append(s, current, s.length()) |
| .append("\\E") |
| .toString(); |
| } |
| |
| /** |
| * Recompile the Pattern instance from a stream. The original pattern |
| * string is read in and the object tree is recompiled from it. |
| */ |
| @java.io.Serial |
| private void readObject(java.io.ObjectInputStream s) |
| throws java.io.IOException, ClassNotFoundException { |
| |
| // Read in all fields |
| s.defaultReadObject(); |
| |
| // Android-removed: reimplement matching logic natively via ICU. |
| /* |
| // reset the flags |
| flags0 = flags; |
| |
| // Initialize counts |
| capturingGroupCount = 1; |
| localCount = 0; |
| localTCNCount = 0; |
| */ |
| |
| // Android-changed: Pattern is eagerly compiled() upon construction. |
| /* |
| // if length > 0, the Pattern is lazily compiled |
| if (pattern.isEmpty()) { |
| root = new Start(lastAccept); |
| matchRoot = lastAccept; |
| compiled = true; |
| } |
| */ |
| compile(); |
| } |
| |
| // Android-changed: reimplement matching logic natively via ICU. |
| // Dropped documentation reference to Start and LastNode implementation |
| // details which do not apply on Android. |
| /** |
| * This private constructor is used to create all Patterns. The pattern |
| * string and match flags are all that is needed to completely describe |
| * a Pattern. |
| */ |
| private Pattern(String p, int f) { |
| // BEGIN Android-added: CANON_EQ and UNICODE_CHARACTER_CLASS flags are not supported. |
| if ((f & CANON_EQ) != 0) { |
| throw new IllegalArgumentException("CANON_EQ flag isn't supported"); |
| } |
| if ((f & UNICODE_CHARACTER_CLASS) != 0) { |
| throw new IllegalArgumentException("UNICODE_CHARACTER_CLASS flag not supported"); |
| } |
| // END Android-added: CANON_EQ and UNICODE_CHARACTER_CLASS flags are not supported. |
| if ((f & ~ALL_FLAGS) != 0) { |
| throw new IllegalArgumentException("Unknown flag 0x" |
| + Integer.toHexString(f)); |
| } |
| pattern = p; |
| flags = f; |
| |
| // Android-changed: Pattern is eagerly compiled() upon construction. |
| // BEGIN Android-changed: Reimplement matching logic via ICU4C, and shouldn't overflow. |
| /* |
| // to use UNICODE_CASE if UNICODE_CHARACTER_CLASS present |
| if ((flags & UNICODE_CHARACTER_CLASS) != 0) |
| flags |= UNICODE_CASE; |
| |
| // 'flags' for compiling |
| flags0 = flags; |
| |
| // Reset group index count |
| capturingGroupCount = 1; |
| localCount = 0; |
| localTCNCount = 0; |
| |
| if (!pattern.isEmpty()) { |
| try { |
| compile(); |
| } catch (StackOverflowError soe) { |
| throw error("Stack overflow during pattern compilation"); |
| } |
| } else { |
| root = new Start(lastAccept); |
| matchRoot = lastAccept; |
| } |
| */ |
| compile(); |
| // END Android-changed: Reimplement matching logic via ICU4C, and shouldn't overflow. |
| } |
| |
| // BEGIN Android-removed: Reimplement matching logic via ICU4C. |
| /** |
| * The pattern is converted to normalized form ({@link |
| * java.text.Normalizer.Form#NFC NFC}, canonical decomposition, |
| * followed by canonical composition for the character class |
| * part, and {@link java.text.Normalizer.Form#NFD NFD}, |
| * canonical decomposition for the rest), and then a pure |
| * group is constructed to match canonical equivalences of the |
| * characters. |
| * |
| private static String normalize(String pattern) { |
| int plen = pattern.length(); |
| StringBuilder pbuf = new StringBuilder(plen); |
| char last = 0; |
| int lastStart = 0; |
| char cc = 0; |
| for (int i = 0; i < plen;) { |
| char c = pattern.charAt(i); |
| if (cc == 0 && // top level |
| c == '\\' && i + 1 < plen && pattern.charAt(i + 1) == '\\') { |
| i += 2; last = 0; |
| continue; |
| } |
| if (c == '[' && last != '\\') { |
| if (cc == 0) { |
| if (lastStart < i) |
| normalizeSlice(pattern, lastStart, i, pbuf); |
| lastStart = i; |
| } |
| cc++; |
| } else if (c == ']' && last != '\\') { |
| cc--; |
| if (cc == 0) { |
| normalizeClazz(pattern, lastStart, i + 1, pbuf); |
| lastStart = i + 1; |
| } |
| } |
| last = c; |
| i++; |
| } |
| assert (cc == 0); |
| if (lastStart < plen) |
| normalizeSlice(pattern, lastStart, plen, pbuf); |
| return pbuf.toString(); |
| } |
| |
| private static void normalizeSlice(String src, int off, int limit, |
| StringBuilder dst) |
| { |
| int len = src.length(); |
| int off0 = off; |
| while (off < limit && ASCII.isAscii(src.charAt(off))) { |
| off++; |
| } |
| if (off == limit) { |
| dst.append(src, off0, limit); |
| return; |
| } |
| off--; |
| if (off < off0) |
| off = off0; |
| else |
| dst.append(src, off0, off); |
| while (off < limit) { |
| int ch0 = src.codePointAt(off); |
| if (".$|()[]{}^?*+\\".indexOf(ch0) != -1) { |
| dst.append((char)ch0); |
| off++; |
| continue; |
| } |
| int j = Grapheme.nextBoundary(src, off, limit); |
| int ch1; |
| String seq = src.substring(off, j); |
| String nfd = Normalizer.normalize(seq, Normalizer.Form.NFD); |
| off = j; |
| if (nfd.codePointCount(0, nfd.length()) > 1) { |
| ch0 = nfd.codePointAt(0); |
| ch1 = nfd.codePointAt(Character.charCount(ch0)); |
| if (Character.getType(ch1) == Character.NON_SPACING_MARK) { |
| Set<String> altns = new LinkedHashSet<>(); |
| altns.add(seq); |
| produceEquivalentAlternation(nfd, altns); |
| dst.append("(?:"); |
| altns.forEach( s -> dst.append(s).append('|')); |
| dst.delete(dst.length() - 1, dst.length()); |
| dst.append(")"); |
| continue; |
| } |
| } |
| String nfc = Normalizer.normalize(seq, Normalizer.Form.NFC); |
| if (!seq.equals(nfc) && !nfd.equals(nfc)) |
| dst.append("(?:" + seq + "|" + nfd + "|" + nfc + ")"); |
| else if (!seq.equals(nfd)) |
| dst.append("(?:" + seq + "|" + nfd + ")"); |
| else |
| dst.append(seq); |
| } |
| } |
| |
| private static void normalizeClazz(String src, int off, int limit, |
| StringBuilder dst) |
| { |
| dst.append(Normalizer.normalize(src.substring(off, limit), Form.NFC)); |
| } |
| |
| /** |
| * Given a specific sequence composed of a regular character and |
| * combining marks that follow it, produce the alternation that will |
| * match all canonical equivalences of that sequence. |
| * |
| private static void produceEquivalentAlternation(String src, |
| Set<String> dst) |
| { |
| int len = countChars(src, 0, 1); |
| if (src.length() == len) { |
| dst.add(src); // source has one character. |
| return; |
| } |
| String base = src.substring(0,len); |
| String combiningMarks = src.substring(len); |
| String[] perms = producePermutations(combiningMarks); |
| // Add combined permutations |
| for(int x = 0; x < perms.length; x++) { |
| String next = base + perms[x]; |
| dst.add(next); |
| next = composeOneStep(next); |
| if (next != null) { |
| produceEquivalentAlternation(next, dst); |
| } |
| } |
| } |
| |
| /** |
| * Returns an array of strings that have all the possible |
| * permutations of the characters in the input string. |
| * This is used to get a list of all possible orderings |
| * of a set of combining marks. Note that some of the permutations |
| * are invalid because of combining class collisions, and these |
| * possibilities must be removed because they are not canonically |
| * equivalent. |
| * |
| private static String[] producePermutations(String input) { |
| if (input.length() == countChars(input, 0, 1)) |
| return new String[] {input}; |
| |
| if (input.length() == countChars(input, 0, 2)) { |
| int c0 = Character.codePointAt(input, 0); |
| int c1 = Character.codePointAt(input, Character.charCount(c0)); |
| if (getClass(c1) == getClass(c0)) { |
| return new String[] {input}; |
| } |
| String[] result = new String[2]; |
| result[0] = input; |
| StringBuilder sb = new StringBuilder(2); |
| sb.appendCodePoint(c1); |
| sb.appendCodePoint(c0); |
| result[1] = sb.toString(); |
| return result; |
| } |
| |
| int length = 1; |
| int nCodePoints = countCodePoints(input); |
| for(int x=1; x<nCodePoints; x++) |
| length = length * (x+1); |
| |
| String[] temp = new String[length]; |
| |
| int combClass[] = new int[nCodePoints]; |
| for(int x=0, i=0; x<nCodePoints; x++) { |
| int c = Character.codePointAt(input, i); |
| combClass[x] = getClass(c); |
| i += Character.charCount(c); |
| } |
| |
| // For each char, take it out and add the permutations |
| // of the remaining chars |
| int index = 0; |
| int len; |
| // offset maintains the index in code units. |
| loop: for(int x=0, offset=0; x<nCodePoints; x++, offset+=len) { |
| len = countChars(input, offset, 1); |
| for(int y=x-1; y>=0; y--) { |
| if (combClass[y] == combClass[x]) { |
| continue loop; |
| } |
| } |
| StringBuilder sb = new StringBuilder(input); |
| String otherChars = sb.delete(offset, offset+len).toString(); |
| String[] subResult = producePermutations(otherChars); |
| |
| String prefix = input.substring(offset, offset+len); |
| for (String sre : subResult) |
| temp[index++] = prefix + sre; |
| } |
| String[] result = new String[index]; |
| System.arraycopy(temp, 0, result, 0, index); |
| return result; |
| } |
| |
| private static int getClass(int c) { |
| return sun.text.Normalizer.getCombiningClass(c); |
| } |
| |
| /** |
| * Attempts to compose input by combining the first character |
| * with the first combining mark following it. Returns a String |
| * that is the composition of the leading character with its first |
| * combining mark followed by the remaining combining marks. Returns |
| * null if the first two characters cannot be further composed. |
| * |
| private static String composeOneStep(String input) { |
| int len = countChars(input, 0, 2); |
| String firstTwoCharacters = input.substring(0, len); |
| String result = Normalizer.normalize(firstTwoCharacters, Normalizer.Form.NFC); |
| if (result.equals(firstTwoCharacters)) |
| return null; |
| else { |
| String remainder = input.substring(len); |
| return result + remainder; |
| } |
| } |
| |
| /** |
| * Preprocess any \Q...\E sequences in `temp', meta-quoting them. |
| * See the description of `quotemeta' in perlfunc(1). |
| * |
| private void RemoveQEQuoting() { |
| final int pLen = patternLength; |
| int i = 0; |
| while (i < pLen-1) { |
| if (temp[i] != '\\') |
| i += 1; |
| else if (temp[i + 1] != 'Q') |
| i += 2; |
| else |
| break; |
| } |
| if (i >= pLen - 1) // No \Q sequence found |
| return; |
| int j = i; |
| i += 2; |
| int newTempLen; |
| try { |
| newTempLen = Math.addExact(j + 2, Math.multiplyExact(3, pLen - i)); |
| } catch (ArithmeticException ae) { |
| throw new OutOfMemoryError("Required pattern length too large"); |
| } |
| int[] newtemp = new int[newTempLen]; |
| System.arraycopy(temp, 0, newtemp, 0, j); |
| |
| boolean inQuote = true; |
| boolean beginQuote = true; |
| while (i < pLen) { |
| int c = temp[i++]; |
| if (!ASCII.isAscii(c) || ASCII.isAlpha(c)) { |
| newtemp[j++] = c; |
| } else if (ASCII.isDigit(c)) { |
| if (beginQuote) { |
| /* |
| * A unicode escape \[0xu] could be before this quote, |
| * and we don't want this numeric char to processed as |
| * part of the escape. |
| * |
| newtemp[j++] = '\\'; |
| newtemp[j++] = 'x'; |
| newtemp[j++] = '3'; |
| } |
| newtemp[j++] = c; |
| } else if (c != '\\') { |
| if (inQuote) newtemp[j++] = '\\'; |
| newtemp[j++] = c; |
| } else if (inQuote) { |
| if (temp[i] == 'E') { |
| i++; |
| inQuote = false; |
| } else { |
| newtemp[j++] = '\\'; |
| newtemp[j++] = '\\'; |
| } |
| } else { |
| if (temp[i] == 'Q') { |
| i++; |
| inQuote = true; |
| beginQuote = true; |
| continue; |
| } else { |
| newtemp[j++] = c; |
| if (i != pLen) |
| newtemp[j++] = temp[i++]; |
| } |
| } |
| |
| beginQuote = false; |
| } |
| |
| patternLength = j; |
| temp = Arrays.copyOf(newtemp, j + 2); // double zero termination |
| } |
| |
| /** |
| * Copies regular expression to an int array and invokes the parsing |
| * of the expression which will create the object tree. |
| * |
| private void compile() { |
| // Handle canonical equivalences |
| if (has(CANON_EQ) && !has(LITERAL)) { |
| normalizedPattern = normalize(pattern); |
| } else { |
| normalizedPattern = pattern; |
| } |
| patternLength = normalizedPattern.length(); |
| |
| // Copy pattern to int array for convenience |
| // Use double zero to terminate pattern |
| temp = new int[patternLength + 2]; |
| |
| hasSupplementary = false; |
| int c, count = 0; |
| // Convert all chars into code points |
| for (int x = 0; x < patternLength; x += Character.charCount(c)) { |
| c = normalizedPattern.codePointAt(x); |
| if (isSupplementary(c)) { |
| hasSupplementary = true; |
| } |
| temp[count++] = c; |
| } |
| |
| patternLength = count; // patternLength now in code points |
| |
| if (! has(LITERAL)) |
| RemoveQEQuoting(); |
| |
| // Allocate all temporary objects here. |
| buffer = new int[32]; |
| groupNodes = new GroupHead[10]; |
| namedGroups = null; |
| topClosureNodes = new ArrayList<>(10); |
| |
| if (has(LITERAL)) { |
| // Literal pattern handling |
| matchRoot = newSlice(temp, patternLength, hasSupplementary); |
| matchRoot.next = lastAccept; |
| } else { |
| // Start recursive descent parsing |
| matchRoot = expr(lastAccept); |
| // Check extra pattern characters |
| if (patternLength != cursor) { |
| if (peek() == ')') { |
| throw error("Unmatched closing ')'"); |
| } else { |
| throw error("Unexpected internal error"); |
| } |
| } |
| } |
| |
| // Peephole optimization |
| if (matchRoot instanceof Slice) { |
| root = BnM.optimize(matchRoot); |
| if (root == matchRoot) { |
| root = hasSupplementary ? new StartS(matchRoot) : new Start(matchRoot); |
| } |
| } else if (matchRoot instanceof Begin || matchRoot instanceof First) { |
| root = matchRoot; |
| } else { |
| root = hasSupplementary ? new StartS(matchRoot) : new Start(matchRoot); |
| } |
| |
| // Optimize the greedy Loop to prevent exponential backtracking, IF there |
| // is no group ref in this pattern. With a non-negative localTCNCount value, |
| // the greedy type Loop, Curly will skip the backtracking for any starting |
| // position "i" that failed in the past. |
| if (!hasGroupRef) { |
| for (Node node : topClosureNodes) { |
| if (node instanceof Loop) { |
| // non-deterministic-greedy-group |
| ((Loop)node).posIndex = localTCNCount++; |
| } |
| } |
| } |
| |
| // Release temporary storage |
| temp = null; |
| buffer = null; |
| groupNodes = null; |
| patternLength = 0; |
| compiled = true; |
| topClosureNodes = null; |
| } |
| |
| Map<String, Integer> namedGroups() { |
| Map<String, Integer> groups = namedGroups; |
| if (groups == null) { |
| namedGroups = groups = new HashMap<>(2); |
| } |
| return groups; |
| } |
| |
| /** |
| * Used to accumulate information about a subtree of the object graph |
| * so that optimizations can be applied to the subtree. |
| * |
| static final class TreeInfo { |
| int minLength; |
| int maxLength; |
| boolean maxValid; |
| boolean deterministic; |
| |
| TreeInfo() { |
| reset(); |
| } |
| void reset() { |
| minLength = 0; |
| maxLength = 0; |
| maxValid = true; |
| deterministic = true; |
| } |
| } |
| |
| /* |
| * The following private methods are mainly used to improve the |
| * readability of the code. In order to let the Java compiler easily |
| * inline them, we should not put many assertions or error checks in them. |
| * |
| |
| /** |
| * Indicates whether a particular flag is set or not. |
| * |
| private boolean has(int f) { |
| return (flags0 & f) != 0; |
| } |
| |
| /** |
| * Match next character, signal error if failed. |
| * |
| private void accept(int ch, String s) { |
| int testChar = temp[cursor++]; |
| if (has(COMMENTS)) |
| testChar = parsePastWhitespace(testChar); |
| if (ch != testChar) { |
| throw error(s); |
| } |
| } |
| |
| /** |
| * Mark the end of pattern with a specific character. |
| * |
| private void mark(int c) { |
| temp[patternLength] = c; |
| } |
| |
| /** |
| * Peek the next character, and do not advance the cursor. |
| * |
| private int peek() { |
| int ch = temp[cursor]; |
| if (has(COMMENTS)) |
| ch = peekPastWhitespace(ch); |
| return ch; |
| } |
| |
| /** |
| * Read the next character, and advance the cursor by one. |
| * |
| private int read() { |
| int ch = temp[cursor++]; |
| if (has(COMMENTS)) |
| ch = parsePastWhitespace(ch); |
| return ch; |
| } |
| |
| /** |
| * Read the next character, and advance the cursor by one, |
| * ignoring the COMMENTS setting |
| * |
| private int readEscaped() { |
| int ch = temp[cursor++]; |
| return ch; |
| } |
| |
| /** |
| * Advance the cursor by one, and peek the next character. |
| * |
| private int next() { |
| int ch = temp[++cursor]; |
| if (has(COMMENTS)) |
| ch = peekPastWhitespace(ch); |
| return ch; |
| } |
| |
| /** |
| * Advance the cursor by one, and peek the next character, |
| * ignoring the COMMENTS setting |
| * |
| private int nextEscaped() { |
| int ch = temp[++cursor]; |
| return ch; |
| } |
| |
| /** |
| * If in xmode peek past whitespace and comments. |
| * |
| private int peekPastWhitespace(int ch) { |
| while (ASCII.isSpace(ch) || ch == '#') { |
| while (ASCII.isSpace(ch)) |
| ch = temp[++cursor]; |
| if (ch == '#') { |
| ch = peekPastLine(); |
| } |
| } |
| return ch; |
| } |
| |
| /** |
| * If in xmode parse past whitespace and comments. |
| * |
| private int parsePastWhitespace(int ch) { |
| while (ASCII.isSpace(ch) || ch == '#') { |
| while (ASCII.isSpace(ch)) |
| ch = temp[cursor++]; |
| if (ch == '#') |
| ch = parsePastLine(); |
| } |
| return ch; |
| } |
| |
| /** |
| * xmode parse past comment to end of line. |
| * |
| private int parsePastLine() { |
| int ch = temp[cursor++]; |
| while (ch != 0 && !isLineSeparator(ch)) |
| ch = temp[cursor++]; |
| if (ch == 0 && cursor > patternLength) { |
| cursor = patternLength; |
| ch = temp[cursor++]; |
| } |
| return ch; |
| } |
| |
| /** |
| * xmode peek past comment to end of line. |
| * |
| private int peekPastLine() { |
| int ch = temp[++cursor]; |
| while (ch != 0 && !isLineSeparator(ch)) |
| ch = temp[++cursor]; |
| if (ch == 0 && cursor > patternLength) { |
| cursor = patternLength; |
| ch = temp[cursor]; |
| } |
| return ch; |
| } |
| |
| /** |
| * Determines if character is a line separator in the current mode |
| * |
| private boolean isLineSeparator(int ch) { |
| if (has(UNIX_LINES)) { |
| return ch == '\n'; |
| } else { |
| return (ch == '\n' || |
| ch == '\r' || |
| (ch|1) == '\u2029' || |
| ch == '\u0085'); |
| } |
| } |
| |
| /** |
| * Read the character after the next one, and advance the cursor by two. |
| * |
| private int skip() { |
| int i = cursor; |
| int ch = temp[i+1]; |
| cursor = i + 2; |
| return ch; |
| } |
| |
| /** |
| * Unread one next character, and retreat cursor by one. |
| * |
| private void unread() { |
| cursor--; |
| } |
| |
| /** |
| * Internal method used for handling all syntax errors. The pattern is |
| * displayed with a pointer to aid in locating the syntax error. |
| * |
| private PatternSyntaxException error(String s) { |
| return new PatternSyntaxException(s, normalizedPattern, cursor - 1); |
| } |
| |
| /** |
| * Determines if there is any supplementary character or unpaired |
| * surrogate in the specified range. |
| * |
| private boolean findSupplementary(int start, int end) { |
| for (int i = start; i < end; i++) { |
| if (isSupplementary(temp[i])) |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * Determines if the specified code point is a supplementary |
| * character or unpaired surrogate. |
| * |
| private static final boolean isSupplementary(int ch) { |
| return ch >= Character.MIN_SUPPLEMENTARY_CODE_POINT || |
| Character.isSurrogate((char)ch); |
| } |
| |
| /** |
| * The following methods handle the main parsing. They are sorted |
| * according to their precedence order, the lowest one first. |
| * |
| |
| /** |
| * The expression is parsed with branch nodes added for alternations. |
| * This may be called recursively to parse sub expressions that may |
| * contain alternations. |
| * |
| private Node expr(Node end) { |
| Node prev = null; |
| Node firstTail = null; |
| Branch branch = null; |
| Node branchConn = null; |
| |
| for (;;) { |
| Node node = sequence(end); |
| Node nodeTail = root; //double return |
| if (prev == null) { |
| prev = node; |
| firstTail = nodeTail; |
| } else { |
| // Branch |
| if (branchConn == null) { |
| branchConn = new BranchConn(); |
| branchConn.next = end; |
| } |
| if (node == end) { |
| // if the node returned from sequence() is "end" |
| // we have an empty expr, set a null atom into |
| // the branch to indicate to go "next" directly. |
| node = null; |
| } else { |
| // the "tail.next" of each atom goes to branchConn |
| nodeTail.next = branchConn; |
| } |
| if (prev == branch) { |
| branch.add(node); |
| } else { |
| if (prev == end) { |
| prev = null; |
| } else { |
| // replace the "end" with "branchConn" at its tail.next |
| // when put the "prev" into the branch as the first atom. |
| firstTail.next = branchConn; |
| } |
| prev = branch = new Branch(prev, node, branchConn); |
| } |
| } |
| if (peek() != '|') { |
| return prev; |
| } |
| next(); |
| } |
| } |
| |
| @SuppressWarnings("fallthrough") |
| /** |
| * Parsing of sequences between alternations. |
| * |
| private Node sequence(Node end) { |
| Node head = null; |
| Node tail = null; |
| Node node; |
| LOOP: |
| for (;;) { |
| int ch = peek(); |
| switch (ch) { |
| case '(': |
| // Because group handles its own closure, |
| // we need to treat it differently |
| node = group0(); |
| // Check for comment or flag group |
| if (node == null) |
| continue; |
| if (head == null) |
| head = node; |
| else |
| tail.next = node; |
| // Double return: Tail was returned in root |
| tail = root; |
| continue; |
| case '[': |
| if (has(CANON_EQ) && !has(LITERAL)) |
| node = new NFCCharProperty(clazz(true)); |
| else |
| node = newCharProperty(clazz(true)); |
| break; |
| case '\\': |
| ch = nextEscaped(); |
| if (ch == 'p' || ch == 'P') { |
| boolean oneLetter = true; |
| boolean comp = (ch == 'P'); |
| ch = next(); // Consume { if present |
| if (ch != '{') { |
| unread(); |
| } else { |
| oneLetter = false; |
| } |
| // node = newCharProperty(family(oneLetter, comp)); |
| if (has(CANON_EQ) && !has(LITERAL)) |
| node = new NFCCharProperty(family(oneLetter, comp)); |
| else |
| node = newCharProperty(family(oneLetter, comp)); |
| } else { |
| unread(); |
| node = atom(); |
| } |
| break; |
| case '^': |
| next(); |
| if (has(MULTILINE)) { |
| if (has(UNIX_LINES)) |
| node = new UnixCaret(); |
| else |
| node = new Caret(); |
| } else { |
| node = new Begin(); |
| } |
| break; |
| case '$': |
| next(); |
| if (has(UNIX_LINES)) |
| node = new UnixDollar(has(MULTILINE)); |
| else |
| node = new Dollar(has(MULTILINE)); |
| break; |
| case '.': |
| next(); |
| if (has(DOTALL)) { |
| node = new CharProperty(ALL()); |
| } else { |
| if (has(UNIX_LINES)) { |
| node = new CharProperty(UNIXDOT()); |
| } else { |
| node = new CharProperty(DOT()); |
| } |
| } |
| break; |
| case '|': |
| case ')': |
| break LOOP; |
| case ']': // Now interpreting dangling ] and } as literals |
| case '}': |
| node = atom(); |
| break; |
| case '?': |
| case '*': |
| case '+': |
| next(); |
| throw error("Dangling meta character '" + ((char)ch) + "'"); |
| case 0: |
| if (cursor >= patternLength) { |
| break LOOP; |
| } |
| // Fall through |
| default: |
| node = atom(); |
| break; |
| } |
| |
| node = closure(node); |
| /* save the top dot-greedy nodes (.*, .+) as well |
| if (node instanceof GreedyCharProperty && |
| ((GreedyCharProperty)node).cp instanceof Dot) { |
| topClosureNodes.add(node); |
| } |
| * |
| if (head == null) { |
| head = tail = node; |
| } else { |
| tail.next = node; |
| tail = node; |
| } |
| } |
| if (head == null) { |
| return end; |
| } |
| tail.next = end; |
| root = tail; //double return |
| return head; |
| } |
| |
| @SuppressWarnings("fallthrough") |
| /** |
| * Parse and add a new Single or Slice. |
| * |
| private Node atom() { |
| int first = 0; |
| int prev = -1; |
| boolean hasSupplementary = false; |
| int ch = peek(); |
| for (;;) { |
| switch (ch) { |
| case '*': |
| case '+': |
| case '?': |
| case '{': |
| if (first > 1) { |
| cursor = prev; // Unwind one character |
| first--; |
| } |
| break; |
| case '$': |
| case '.': |
| case '^': |
| case '(': |
| case '[': |
| case '|': |
| case ')': |
| break; |
| case '\\': |
| ch = nextEscaped(); |
| if (ch == 'p' || ch == 'P') { // Property |
| if (first > 0) { // Slice is waiting; handle it first |
| unread(); |
| break; |
| } else { // No slice; just return the family node |
| boolean comp = (ch == 'P'); |
| boolean oneLetter = true; |
| ch = next(); // Consume { if present |
| if (ch != '{') |
| unread(); |
| else |
| oneLetter = false; |
| if (has(CANON_EQ) && !has(LITERAL)) |
| return new NFCCharProperty(family(oneLetter, comp)); |
| else |
| return newCharProperty(family(oneLetter, comp)); |
| } |
| } |
| unread(); |
| prev = cursor; |
| ch = escape(false, first == 0, false); |
| if (ch >= 0) { |
| append(ch, first); |
| first++; |
| if (isSupplementary(ch)) { |
| hasSupplementary = true; |
| } |
| ch = peek(); |
| continue; |
| } else if (first == 0) { |
| return root; |
| } |
| // Unwind meta escape sequence |
| cursor = prev; |
| break; |
| case 0: |
| if (cursor >= patternLength) { |
| break; |
| } |
| // Fall through |
| default: |
| prev = cursor; |
| append(ch, first); |
| first++; |
| if (isSupplementary(ch)) { |
| hasSupplementary = true; |
| } |
| ch = next(); |
| continue; |
| } |
| break; |
| } |
| if (first == 1) { |
| return newCharProperty(single(buffer[0])); |
| } else { |
| return newSlice(buffer, first, hasSupplementary); |
| } |
| } |
| |
| private void append(int ch, int index) { |
| int len = buffer.length; |
| if (index - len >= 0) { |
| len = ArraysSupport.newLength(len, |
| 1 + index - len, /* minimum growth * / |
| len /* preferred growth * /); |
| buffer = Arrays.copyOf(buffer, len); |
| } |
| buffer[index] = ch; |
| } |
| |
| /** |
| * Parses a backref greedily, taking as many numbers as it |
| * can. The first digit is always treated as a backref, but |
| * multi digit numbers are only treated as a backref if at |
| * least that many backrefs exist at this point in the regex. |
| * |
| private Node ref(int refNum) { |
| boolean done = false; |
| while(!done) { |
| int ch = peek(); |
| switch (ch) { |
| case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' -> { |
| int newRefNum = (refNum * 10) + (ch - '0'); |
| // Add another number if it doesn't make a group |
| // that doesn't exist |
| if (capturingGroupCount - 1 < newRefNum) { |
| done = true; |
| break; |
| } |
| refNum = newRefNum; |
| read(); |
| } |
| default -> done = true; |
| } |
| } |
| hasGroupRef = true; |
| if (has(CASE_INSENSITIVE)) |
| return new CIBackRef(refNum, has(UNICODE_CASE)); |
| else |
| return new BackRef(refNum); |
| } |
| |
| /** |
| * Parses an escape sequence to determine the actual value that needs |
| * to be matched. |
| * If -1 is returned and create was true a new object was added to the tree |
| * to handle the escape sequence. |
| * If the returned value is greater than zero, it is the value that |
| * matches the escape sequence. |
| * |
| private int escape(boolean inclass, boolean create, boolean isrange) { |
| int ch = skip(); |
| switch (ch) { |
| case '0': |
| return o(); |
| case '1': |
| case '2': |
| case '3': |
| case '4': |
| case '5': |
| case '6': |
| case '7': |
| case '8': |
| case '9': |
| if (inclass) break; |
| if (create) { |
| root = ref((ch - '0')); |
| } |
| return -1; |
| case 'A': |
| if (inclass) break; |
| if (create) root = new Begin(); |
| return -1; |
| case 'B': |
| if (inclass) break; |
| if (create) root = new Bound(Bound.NONE, has(UNICODE_CHARACTER_CLASS)); |
| return -1; |
| case 'C': |
| break; |
| case 'D': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.DIGIT() : CharPredicates.ASCII_DIGIT(); |
| predicate = predicate.negate(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'E': |
| case 'F': |
| break; |
| case 'G': |
| if (inclass) break; |
| if (create) root = new LastMatch(); |
| return -1; |
| case 'H': |
| if (create) { |
| predicate = HorizWS().negate(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'I': |
| case 'J': |
| case 'K': |
| case 'L': |
| case 'M': |
| break; |
| case 'N': |
| return N(); |
| case 'O': |
| case 'P': |
| case 'Q': |
| break; |
| case 'R': |
| if (inclass) break; |
| if (create) root = new LineEnding(); |
| return -1; |
| case 'S': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.WHITE_SPACE() : CharPredicates.ASCII_SPACE(); |
| predicate = predicate.negate(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'T': |
| case 'U': |
| break; |
| case 'V': |
| if (create) { |
| predicate = VertWS().negate(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'W': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.WORD() : CharPredicates.ASCII_WORD(); |
| predicate = predicate.negate(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'X': |
| if (inclass) break; |
| if (create) { |
| root = new XGrapheme(); |
| } |
| return -1; |
| case 'Y': |
| break; |
| case 'Z': |
| if (inclass) break; |
| if (create) { |
| if (has(UNIX_LINES)) |
| root = new UnixDollar(false); |
| else |
| root = new Dollar(false); |
| } |
| return -1; |
| case 'a': |
| return '\007'; |
| case 'b': |
| if (inclass) break; |
| if (create) { |
| if (peek() == '{') { |
| if (skip() == 'g') { |
| if (read() == '}') { |
| root = new GraphemeBound(); |
| return -1; |
| } |
| break; // error missing trailing } |
| } |
| unread(); unread(); |
| } |
| root = new Bound(Bound.BOTH, has(UNICODE_CHARACTER_CLASS)); |
| } |
| return -1; |
| case 'c': |
| return c(); |
| case 'd': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.DIGIT() : CharPredicates.ASCII_DIGIT(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'e': |
| return '\033'; |
| case 'f': |
| return '\f'; |
| case 'g': |
| break; |
| case 'h': |
| if (create) { |
| predicate = HorizWS(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'i': |
| case 'j': |
| break; |
| case 'k': |
| if (inclass) |
| break; |
| if (read() != '<') |
| throw error("\\k is not followed by '<' for named capturing group"); |
| String name = groupname(read()); |
| if (!namedGroups().containsKey(name)) |
| throw error("named capturing group <" + name + "> does not exist"); |
| if (create) { |
| hasGroupRef = true; |
| if (has(CASE_INSENSITIVE)) |
| root = new CIBackRef(namedGroups().get(name), has(UNICODE_CASE)); |
| else |
| root = new BackRef(namedGroups().get(name)); |
| } |
| return -1; |
| case 'l': |
| case 'm': |
| break; |
| case 'n': |
| return '\n'; |
| case 'o': |
| case 'p': |
| case 'q': |
| break; |
| case 'r': |
| return '\r'; |
| case 's': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.WHITE_SPACE() : CharPredicates.ASCII_SPACE(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 't': |
| return '\t'; |
| case 'u': |
| return u(); |
| case 'v': |
| // '\v' was implemented as VT/0x0B in releases < 1.8 (though |
| // undocumented). In JDK8 '\v' is specified as a predefined |
| // character class for all vertical whitespace characters. |
| // So [-1, root=VertWS node] pair is returned (instead of a |
| // single 0x0B). This breaks the range if '\v' is used as |
| // the start or end value, such as [\v-...] or [...-\v], in |
| // which a single definite value (0x0B) is expected. For |
| // compatibility concern '\013'/0x0B is returned if isrange. |
| if (isrange) |
| return '\013'; |
| if (create) { |
| predicate = VertWS(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'w': |
| if (create) { |
| predicate = has(UNICODE_CHARACTER_CLASS) ? |
| CharPredicates.WORD() : CharPredicates.ASCII_WORD(); |
| if (!inclass) |
| root = newCharProperty(predicate); |
| } |
| return -1; |
| case 'x': |
| return x(); |
| case 'y': |
| break; |
| case 'z': |
| if (inclass) break; |
| if (create) root = new End(); |
| return -1; |
| default: |
| return ch; |
| } |
| throw error("Illegal/unsupported escape sequence"); |
| } |
| |
| /** |
| * Parse a character class, and return the node that matches it. |
| * |
| * Consumes a ] on the way out if consume is true. Usually consume |
| * is true except for the case of [abc&&def] where def is a separate |
| * right hand node with "understood" brackets. |
| * |
| private CharPredicate clazz(boolean consume) { |
| CharPredicate prev = null; |
| CharPredicate curr = null; |
| BitClass bits = new BitClass(); |
| |
| boolean isNeg = false; |
| boolean hasBits = false; |
| int ch = next(); |
| |
| // Negates if first char in a class, otherwise literal |
| if (ch == '^' && temp[cursor-1] == '[') { |
| ch = next(); |
| isNeg = true; |
| } |
| for (;;) { |
| switch (ch) { |
| case '[': |
| curr = clazz(true); |
| if (prev == null) |
| prev = curr; |
| else |
| prev = prev.union(curr); |
| ch = peek(); |
| continue; |
| case '&': |
| ch = next(); |
| if (ch == '&') { |
| ch = next(); |
| CharPredicate right = null; |
| while (ch != ']' && ch != '&') { |
| if (ch == '[') { |
| if (right == null) |
| right = clazz(true); |
| else |
| right = right.union(clazz(true)); |
| } else { // abc&&def |
| unread(); |
| if (right == null) { |
| right = clazz(false); |
| } else { |
| right = right.union(clazz(false)); |
| } |
| } |
| ch = peek(); |
| } |
| if (hasBits) { |
| // bits used, union has high precedence |
| if (prev == null) { |
| prev = curr = bits; |
| } else { |
| prev = prev.union(bits); |
| } |
| hasBits = false; |
| } |
| if (right != null) |
| curr = right; |
| if (prev == null) { |
| if (right == null) |
| throw error("Bad class syntax"); |
| else |
| prev = right; |
| } else { |
| prev = prev.and(curr); |
| } |
| } else { |
| // treat as a literal & |
| unread(); |
| break; |
| } |
| continue; |
| case 0: |
| if (cursor >= patternLength) |
| throw error("Unclosed character class"); |
| break; |
| case ']': |
| if (prev != null || hasBits) { |
| if (consume) |
| next(); |
| if (prev == null) |
| prev = bits; |
| else if (hasBits) |
| prev = prev.union(bits); |
| if (isNeg) |
| return prev.negate(); |
| return prev; |
| } |
| break; |
| default: |
| break; |
| } |
| curr = range(bits); |
| if (curr == null) { // the bits used |
| hasBits = true; |
| } else { |
| if (prev == null) |
| prev = curr; |
| else if (prev != curr) |
| prev = prev.union(curr); |
| } |
| ch = peek(); |
| } |
| } |
| |
| private CharPredicate bitsOrSingle(BitClass bits, int ch) { |
| /* Bits can only handle codepoints in [u+0000-u+00ff] range. |
| Use "single" node instead of bits when dealing with unicode |
| case folding for codepoints listed below. |
| (1)Uppercase out of range: u+00ff, u+00b5 |
| toUpperCase(u+00ff) -> u+0178 |
| toUpperCase(u+00b5) -> u+039c |
| (2)LatinSmallLetterLongS u+17f |
| toUpperCase(u+017f) -> u+0053 |
| (3)LatinSmallLetterDotlessI u+131 |
| toUpperCase(u+0131) -> u+0049 |
| (4)LatinCapitalLetterIWithDotAbove u+0130 |
| toLowerCase(u+0130) -> u+0069 |
| (5)KelvinSign u+212a |
| toLowerCase(u+212a) ==> u+006B |
| (6)AngstromSign u+212b |
| toLowerCase(u+212b) ==> u+00e5 |
| * |
| if (ch < 256 && |
| !(has(CASE_INSENSITIVE) && has(UNICODE_CASE) && |
| (ch == 0xff || ch == 0xb5 || |
| ch == 0x49 || ch == 0x69 || //I and i |
| ch == 0x53 || ch == 0x73 || //S and s |
| ch == 0x4b || ch == 0x6b || //K and k |
| ch == 0xc5 || ch == 0xe5))) { //A+ring |
| bits.add(ch, flags0); |
| return null; |
| } |
| return single(ch); |
| } |
| |
| /** |
| * Returns a suitably optimized, single character predicate |
| * |
| private CharPredicate single(final int ch) { |
| if (has(CASE_INSENSITIVE)) { |
| int lower, upper; |
| if (has(UNICODE_CASE)) { |
| upper = Character.toUpperCase(ch); |
| lower = Character.toLowerCase(upper); |
| // Unicode case insensitive matches |
| if (upper != lower) |
| return SingleU(lower); |
| } else if (ASCII.isAscii(ch)) { |
| lower = ASCII.toLower(ch); |
| upper = ASCII.toUpper(ch); |
| // Case insensitive matches a given BMP character |
| if (lower != upper) |
| return SingleI(lower, upper); |
| } |
| } |
| if (isSupplementary(ch)) |
| return SingleS(ch); |
| return Single(ch); // Match a given BMP character |
| } |
| |
| /** |
| * Parse a single character or a character range in a character class |
| * and return its representative node. |
| * |
| private CharPredicate range(BitClass bits) { |
| int ch = peek(); |
| if (ch == '\\') { |
| ch = nextEscaped(); |
| if (ch == 'p' || ch == 'P') { // A property |
| boolean comp = (ch == 'P'); |
| boolean oneLetter = true; |
| // Consume { if present |
| ch = next(); |
| if (ch != '{') |
| unread(); |
| else |
| oneLetter = false; |
| return family(oneLetter, comp); |
| } else { // ordinary escape |
| boolean isrange = temp[cursor+1] == '-'; |
| unread(); |
| ch = escape(true, true, isrange); |
| if (ch == -1) |
| return predicate; |
| } |
| } else { |
| next(); |
| } |
| if (ch >= 0) { |
| if (peek() == '-') { |
| int endRange = temp[cursor+1]; |
| if (endRange == '[') { |
| return bitsOrSingle(bits, ch); |
| } |
| if (endRange != ']') { |
| next(); |
| int m = peek(); |
| if (m == '\\') { |
| m = escape(true, false, true); |
| } else { |
| next(); |
| } |
| if (m < ch) { |
| throw error("Illegal character range"); |
| } |
| if (has(CASE_INSENSITIVE)) { |
| if (has(UNICODE_CASE)) |
| return CIRangeU(ch, m); |
| return CIRange(ch, m); |
| } else { |
| return Range(ch, m); |
| } |
| } |
| } |
| return bitsOrSingle(bits, ch); |
| } |
| throw error("Unexpected character '"+((char)ch)+"'"); |
| } |
| |
| /** |
| * Parses a Unicode character family and returns its representative node. |
| * |
| private CharPredicate family(boolean singleLetter, boolean isComplement) { |
| next(); |
| String name; |
| CharPredicate p = null; |
| |
| if (singleLetter) { |
| int c = temp[cursor]; |
| if (!Character.isSupplementaryCodePoint(c)) { |
| name = String.valueOf((char)c); |
| } else { |
| name = new String(temp, cursor, 1); |
| } |
| read(); |
| } else { |
| int i = cursor; |
| mark('}'); |
| while(read() != '}') { |
| } |
| mark('\000'); |
| int j = cursor; |
| if (j > patternLength) |
| throw error("Unclosed character family"); |
| if (i + 1 >= j) |
| throw error("Empty character family"); |
| name = new String(temp, i, j-i-1); |
| } |
| |
| int i = name.indexOf('='); |
| if (i != -1) { |
| // property construct \p{name=value} |
| String value = name.substring(i + 1); |
| name = name.substring(0, i).toLowerCase(Locale.ENGLISH); |
| switch (name) { |
| case "sc": |
| case "script": |
| p = CharPredicates.forUnicodeScript(value); |
| break; |
| case "blk": |
| case "block": |
| p = CharPredicates.forUnicodeBlock(value); |
| break; |
| case "gc": |
| case "general_category": |
| p = CharPredicates.forProperty(value, has(CASE_INSENSITIVE)); |
| break; |
| default: |
| break; |
| } |
| if (p == null) |
| throw error("Unknown Unicode property {name=<" + name + ">, " |
| + "value=<" + value + ">}"); |
| |
| } else { |
| if (name.startsWith("In")) { |
| // \p{InBlockName} |
| p = CharPredicates.forUnicodeBlock(name.substring(2)); |
| } else if (name.startsWith("Is")) { |
| // \p{IsGeneralCategory} and \p{IsScriptName} |
| String shortName = name.substring(2); |
| p = CharPredicates.forUnicodeProperty(shortName, has(CASE_INSENSITIVE)); |
| if (p == null) |
| p = CharPredicates.forProperty(shortName, has(CASE_INSENSITIVE)); |
| if (p == null) |
| p = CharPredicates.forUnicodeScript(shortName); |
| } else { |
| if (has(UNICODE_CHARACTER_CLASS)) |
| p = CharPredicates.forPOSIXName(name, has(CASE_INSENSITIVE)); |
| if (p == null) |
| p = CharPredicates.forProperty(name, has(CASE_INSENSITIVE)); |
| } |
| if (p == null) |
| throw error("Unknown character property name {" + name + "}"); |
| } |
| if (isComplement) { |
| // it might be too expensive to detect if a complement of |
| // CharProperty can match "certain" supplementary. So just |
| // go with StartS. |
| hasSupplementary = true; |
| p = p.negate(); |
| } |
| return p; |
| } |
| |
| private CharProperty newCharProperty(CharPredicate p) { |
| if (p == null) |
| return null; |
| if (p instanceof BmpCharPredicate) |
| return new BmpCharProperty((BmpCharPredicate)p); |
| else { |
| hasSupplementary = true; |
| return new CharProperty(p); |
| } |
| } |
| |
| /** |
| * Parses and returns the name of a "named capturing group", the trailing |
| * ">" is consumed after parsing. |
| * |
| private String groupname(int ch) { |
| StringBuilder sb = new StringBuilder(); |
| if (!ASCII.isAlpha(ch)) |
| throw error("capturing group name does not start with a Latin letter"); |
| do { |
| sb.append((char) ch); |
| } while (ASCII.isAlnum(ch=read())); |
| if (ch != '>') |
| throw error("named capturing group is missing trailing '>'"); |
| return sb.toString(); |
| } |
| |
| /** |
| * Parses a group and returns the head node of a set of nodes that process |
| * the group. Sometimes a double return system is used where the tail is |
| * returned in root. |
| * |
| private Node group0() { |
| boolean capturingGroup = false; |
| Node head; |
| Node tail; |
| int save = flags0; |
| int saveTCNCount = topClosureNodes.size(); |
| root = null; |
| int ch = next(); |
| if (ch == '?') { |
| ch = skip(); |
| switch (ch) { |
| case ':' -> { // (?:xxx) pure group |
| head = createGroup(true); |
| tail = root; |
| head.next = expr(tail); |
| } |
| case '=', '!' -> { // (?=xxx) and (?!xxx) lookahead |
| head = createGroup(true); |
| tail = root; |
| head.next = expr(tail); |
| if (ch == '=') { |
| head = tail = new Pos(head); |
| } else { |
| head = tail = new Neg(head); |
| } |
| } |
| case '>' -> { // (?>xxx) independent group |
| head = createGroup(true); |
| tail = root; |
| head.next = expr(tail); |
| head = tail = new Ques(head, Qtype.INDEPENDENT); |
| } |
| case '<' -> { // (?<xxx) look behind |
| ch = read(); |
| if (ch != '=' && ch != '!') { |
| // named captured group |
| String name = groupname(ch); |
| if (namedGroups().containsKey(name)) |
| throw error("Named capturing group <" + name |
| + "> is already defined"); |
| capturingGroup = true; |
| head = createGroup(false); |
| tail = root; |
| namedGroups().put(name, capturingGroupCount - 1); |
| head.next = expr(tail); |
| break; |
| } |
| int start = cursor; |
| head = createGroup(true); |
| tail = root; |
| head.next = expr(tail); |
| tail.next = LookBehindEndNode.INSTANCE; |
| TreeInfo info = new TreeInfo(); |
| head.study(info); |
| if (info.maxValid == false) { |
| throw error("Look-behind group does not have " |
| + "an obvious maximum length"); |
| } |
| boolean hasSupplementary = findSupplementary(start, patternLength); |
| if (ch == '=') { |
| head = tail = (hasSupplementary ? |
| new BehindS(head, info.maxLength, |
| info.minLength) : |
| new Behind(head, info.maxLength, |
| info.minLength)); |
| } else { // if (ch == '!') |
| head = tail = (hasSupplementary ? |
| new NotBehindS(head, info.maxLength, |
| info.minLength) : |
| new NotBehind(head, info.maxLength, |
| info.minLength)); |
| } |
| // clear all top-closure-nodes inside lookbehind |
| if (saveTCNCount < topClosureNodes.size()) |
| topClosureNodes.subList(saveTCNCount, topClosureNodes.size()).clear(); |
| } |
| case '$', '@' -> throw error("Unknown group type"); |
| default -> { // (?xxx:) inlined match flags |
| unread(); |
| addFlag(); |
| ch = read(); |
| if (ch == ')') { |
| return null; // Inline modifier only |
| } |
| if (ch != ':') { |
| throw error("Unknown inline modifier"); |
| } |
| head = createGroup(true); |
| tail = root; |
| head.next = expr(tail); |
| } |
| } |
| } else { // (xxx) a regular group |
| capturingGroup = true; |
| head = createGroup(false); |
| tail = root; |
| head.next = expr(tail); |
| } |
| |
| accept(')', "Unclosed group"); |
| flags0 = save; |
| |
| // Check for quantifiers |
| Node node = closure(head); |
| if (node == head) { // No closure |
| root = tail; |
| return node; // Dual return |
| } |
| if (head == tail) { // Zero length assertion |
| root = node; |
| return node; // Dual return |
| } |
| |
| // have group closure, clear all inner closure nodes from the |
| // top list (no backtracking stopper optimization for inner |
| if (saveTCNCount < topClosureNodes.size()) |
| topClosureNodes.subList(saveTCNCount, topClosureNodes.size()).clear(); |
| |
| if (node instanceof Ques ques) { |
| if (ques.type == Qtype.POSSESSIVE) { |
| root = node; |
| return node; |
| } |
| tail.next = new BranchConn(); |
| tail = tail.next; |
| if (ques.type == Qtype.GREEDY) { |
| head = new Branch(head, null, tail); |
| } else { // Reluctant quantifier |
| head = new Branch(null, head, tail); |
| } |
| root = tail; |
| return head; |
| } else if (node instanceof Curly curly) { |
| if (curly.type == Qtype.POSSESSIVE) { |
| root = node; |
| return node; |
| } |
| // Discover if the group is deterministic |
| TreeInfo info = new TreeInfo(); |
| if (head.study(info)) { // Deterministic |
| GroupTail temp = (GroupTail) tail; |
| head = root = new GroupCurly(head.next, curly.cmin, |
| curly.cmax, curly.type, |
| ((GroupTail)tail).localIndex, |
| ((GroupTail)tail).groupIndex, |
| capturingGroup); |
| return head; |
| } else { // Non-deterministic |
| int temp = ((GroupHead) head).localIndex; |
| Loop loop; |
| if (curly.type == Qtype.GREEDY) { |
| loop = new Loop(this.localCount, temp); |
| // add the max_reps greedy to the top-closure-node list |
| if (curly.cmax == MAX_REPS) |
| topClosureNodes.add(loop); |
| } else { // Reluctant Curly |
| loop = new LazyLoop(this.localCount, temp); |
| } |
| Prolog prolog = new Prolog(loop); |
| this.localCount += 1; |
| loop.cmin = curly.cmin; |
| loop.cmax = curly.cmax; |
| loop.body = head; |
| tail.next = loop; |
| root = loop; |
| return prolog; // Dual return |
| } |
| } |
| throw error("Internal logic error"); |
| } |
| |
| /** |
| * Create group head and tail nodes using double return. If the group is |
| * created with anonymous true then it is a pure group and should not |
| * affect group counting. |
| * |
| private Node createGroup(boolean anonymous) { |
| int localIndex = localCount++; |
| int groupIndex = 0; |
| if (!anonymous) |
| groupIndex = capturingGroupCount++; |
| GroupHead head = new GroupHead(localIndex); |
| root = new GroupTail(localIndex, groupIndex); |
| |
| // for debug/print only, head.match does NOT need the "tail" info |
| head.tail = (GroupTail)root; |
| |
| if (!anonymous && groupIndex < 10) |
| groupNodes[groupIndex] = head; |
| return head; |
| } |
| |
| @SuppressWarnings("fallthrough") |
| /** |
| * Parses inlined match flags and set them appropriately. |
| * |
| private void addFlag() { |
| int ch = peek(); |
| for (;;) { |
| switch (ch) { |
| case 'i': |
| flags0 |= CASE_INSENSITIVE; |
| break; |
| case 'm': |
| flags0 |= MULTILINE; |
| break; |
| case 's': |
| flags0 |= DOTALL; |
| break; |
| case 'd': |
| flags0 |= UNIX_LINES; |
| break; |
| case 'u': |
| flags0 |= UNICODE_CASE; |
| break; |
| case 'c': |
| flags0 |= CANON_EQ; |
| break; |
| case 'x': |
| flags0 |= COMMENTS; |
| break; |
| case 'U': |
| flags0 |= (UNICODE_CHARACTER_CLASS | UNICODE_CASE); |
| break; |
| case '-': // subFlag then fall through |
| ch = next(); |
| subFlag(); |
| default: |
| return; |
| } |
| ch = next(); |
| } |
| } |
| |
| @SuppressWarnings("fallthrough") |
| /** |
| * Parses the second part of inlined match flags and turns off |
| * flags appropriately. |
| * |
| private void subFlag() { |
| int ch = peek(); |
| for (;;) { |
| switch (ch) { |
| case 'i': |
| flags0 &= ~CASE_INSENSITIVE; |
| break; |
| case 'm': |
| flags0 &= ~MULTILINE; |
| break; |
| case 's': |
| flags0 &= ~DOTALL; |
| break; |
| case 'd': |
| flags0 &= ~UNIX_LINES; |
| break; |
| case 'u': |
| flags0 &= ~UNICODE_CASE; |
| break; |
| case 'c': |
| flags0 &= ~CANON_EQ; |
| break; |
| case 'x': |
| flags0 &= ~COMMENTS; |
| break; |
| case 'U': |
| flags0 &= ~(UNICODE_CHARACTER_CLASS | UNICODE_CASE); |
| break; |
| default: |
| return; |
| } |
| ch = next(); |
| } |
| } |
| |
| static final int MAX_REPS = 0x7FFFFFFF; |
| |
| static enum Qtype { |
| GREEDY, LAZY, POSSESSIVE, INDEPENDENT |
| } |
| |
| private Qtype qtype() { |
| int ch = next(); |
| if (ch == '?') { |
| next(); |
| return Qtype.LAZY; |
| } else if (ch == '+') { |
| next(); |
| return Qtype.POSSESSIVE; |
| } |
| return Qtype.GREEDY; |
| } |
| |
| private Node curly(Node prev, int cmin) { |
| Qtype qtype = qtype(); |
| if (qtype == Qtype.GREEDY) { |
| if (prev instanceof BmpCharProperty) { |
| return new BmpCharPropertyGreedy((BmpCharProperty)prev, cmin); |
| } else if (prev instanceof CharProperty) { |
| return new CharPropertyGreedy((CharProperty)prev, cmin); |
| } |
| } |
| return new Curly(prev, cmin, MAX_REPS, qtype); |
| } |
| |
| /** |
| * Processes repetition. If the next character peeked is a quantifier |
| * then new nodes must be appended to handle the repetition. |
| * Prev could be a single or a group, so it could be a chain of nodes. |
| * |
| private Node closure(Node prev) { |
| int ch = peek(); |
| switch (ch) { |
| case '?': |
| return new Ques(prev, qtype()); |
| case '*': |
| return curly(prev, 0); |
| case '+': |
| return curly(prev, 1); |
| case '{': |
| ch = skip(); |
| if (ASCII.isDigit(ch)) { |
| int cmin = 0, cmax; |
| try { |
| do { |
| cmin = Math.addExact(Math.multiplyExact(cmin, 10), |
| ch - '0'); |
| } while (ASCII.isDigit(ch = read())); |
| if (ch == ',') { |
| ch = read(); |
| if (ch == '}') { |
| unread(); |
| return curly(prev, cmin); |
| } else { |
| cmax = 0; |
| while (ASCII.isDigit(ch)) { |
| cmax = Math.addExact(Math.multiplyExact(cmax, 10), |
| ch - '0'); |
| ch = read(); |
| } |
| } |
| } else { |
| cmax = cmin; |
| } |
| } catch (ArithmeticException ae) { |
| throw error("Illegal repetition range"); |
| } |
| if (ch != '}') |
| throw error("Unclosed counted closure"); |
| if (cmax < cmin) |
| throw error("Illegal repetition range"); |
| unread(); |
| return (cmin == 0 && cmax == 1) |
| ? new Ques(prev, qtype()) |
| : new Curly(prev, cmin, cmax, qtype()); |
| } else { |
| throw error("Illegal repetition"); |
| } |
| default: |
| return prev; |
| } |
| } |
| |
| /** |
| * Utility method for parsing control escape sequences. |
| * |
| private int c() { |
| if (cursor < patternLength) { |
| return read() ^ 64; |
| } |
| throw error("Illegal control escape sequence"); |
| } |
| |
| /** |
| * Utility method for parsing octal escape sequences. |
| * |
| private int o() { |
| int n = read(); |
| if (((n-'0')|('7'-n)) >= 0) { |
| int m = read(); |
| if (((m-'0')|('7'-m)) >= 0) { |
| int o = read(); |
| if ((((o-'0')|('7'-o)) >= 0) && (((n-'0')|('3'-n)) >= 0)) { |
| return (n - '0') * 64 + (m - '0') * 8 + (o - '0'); |
| } |
| unread(); |
| return (n - '0') * 8 + (m - '0'); |
| } |
| unread(); |
| return (n - '0'); |
| } |
| throw error("Illegal octal escape sequence"); |
| } |
| |
| /** |
| * Utility method for parsing hexadecimal escape sequences. |
| * |
| private int x() { |
| int n = read(); |
| if (ASCII.isHexDigit(n)) { |
| int m = read(); |
| if (ASCII.isHexDigit(m)) { |
| return ASCII.toDigit(n) * 16 + ASCII.toDigit(m); |
| } |
| } else if (n == '{' && ASCII.isHexDigit(peek())) { |
| int ch = 0; |
| while (ASCII.isHexDigit(n = read())) { |
| ch = (ch << 4) + ASCII.toDigit(n); |
| if (ch > Character.MAX_CODE_POINT) |
| throw error("Hexadecimal codepoint is too big"); |
| } |
| if (n != '}') |
| throw error("Unclosed hexadecimal escape sequence"); |
| return ch; |
| } |
| throw error("Illegal hexadecimal escape sequence"); |
| } |
| |
| /** |
| * Utility method for parsing unicode escape sequences. |
| * |
| private int cursor() { |
| return cursor; |
| } |
| |
| private void setcursor(int pos) { |
| cursor = pos; |
| } |
| |
| private int uxxxx() { |
| int n = 0; |
| for (int i = 0; i < 4; i++) { |
| int ch = read(); |
| if (!ASCII.isHexDigit(ch)) { |
| throw error("Illegal Unicode escape sequence"); |
| } |
| n = n * 16 + ASCII.toDigit(ch); |
| } |
| return n; |
| } |
| |
| private int u() { |
| int n = uxxxx(); |
| if (Character.isHighSurrogate((char)n)) { |
| int cur = cursor(); |
| if (read() == '\\' && read() == 'u') { |
| int n2 = uxxxx(); |
| if (Character.isLowSurrogate((char)n2)) |
| return Character.toCodePoint((char)n, (char)n2); |
| } |
| setcursor(cur); |
| } |
| return n; |
| } |
| |
| private int N() { |
| if (read() == '{') { |
| int i = cursor; |
| while (read() != '}') { |
| if (cursor >= patternLength) |
| throw error("Unclosed character name escape sequence"); |
| } |
| String name = new String(temp, i, cursor - i - 1); |
| try { |
| return Character.codePointOf(name); |
| } catch (IllegalArgumentException x) { |
| throw error("Unknown character name [" + name + "]"); |
| } |
| } |
| throw error("Illegal character name escape sequence"); |
| } |
| |
| // |
| // Utility methods for code point support |
| // |
| private static final int countChars(CharSequence seq, int index, |
| int lengthInCodePoints) { |
| // optimization |
| if (lengthInCodePoints == 1 && index >= 0 && index < seq.length() && |
| !Character.isHighSurrogate(seq.charAt(index))) { |
| return 1; |
| } |
| int length = seq.length(); |
| int x = index; |
| if (lengthInCodePoints >= 0) { |
| assert ((length == 0 && index == 0) || index >= 0 && index < length); |
| for (int i = 0; x < length && i < lengthInCodePoints; i++) { |
| if (Character.isHighSurrogate(seq.charAt(x++))) { |
| if (x < length && Character.isLowSurrogate(seq.charAt(x))) { |
| x++; |
| } |
| } |
| } |
| return x - index; |
| } |
| |
| assert (index >= 0 && index <= length); |
| if (index == 0) { |
| return 0; |
| } |
| int len = -lengthInCodePoints; |
| for (int i = 0; x > 0 && i < len; i++) { |
| if (Character.isLowSurrogate(seq.charAt(--x))) { |
| if (x > 0 && Character.isHighSurrogate(seq.charAt(x-1))) { |
| x--; |
| } |
| } |
| } |
| return index - x; |
| } |
| |
| private static final int countCodePoints(CharSequence seq) { |
| int length = seq.length(); |
| int n = 0; |
| for (int i = 0; i < length; ) { |
| n++; |
| if (Character.isHighSurrogate(seq.charAt(i++))) { |
| if (i < length && Character.isLowSurrogate(seq.charAt(i))) { |
| i++; |
| } |
| } |
| } |
| return n; |
| } |
| |
| /** |
| * Creates a bit vector for matching Latin-1 values. A normal BitClass |
| * never matches values above Latin-1, and a complemented BitClass always |
| * matches values above Latin-1. |
| * |
| static final class BitClass implements BmpCharPredicate { |
| final boolean[] bits; |
| BitClass() { |
| bits = new boolean[256]; |
| } |
| BitClass add(int c, int flags) { |
| assert c >= 0 && c <= 255; |
| if ((flags & CASE_INSENSITIVE) != 0) { |
| if (ASCII.isAscii(c)) { |
| bits[ASCII.toUpper(c)] = true; |
| bits[ASCII.toLower(c)] = true; |
| } else if ((flags & UNICODE_CASE) != 0) { |
| bits[Character.toLowerCase(c)] = true; |
| bits[Character.toUpperCase(c)] = true; |
| } |
| } |
| bits[c] = true; |
| return this; |
| } |
| public boolean is(int ch) { |
| return ch < 256 && bits[ch]; |
| } |
| } |
| |
| |
| /** |
| * Utility method for creating a string slice matcher. |
| * |
| private Node newSlice(int[] buf, int count, boolean hasSupplementary) { |
| int[] tmp = new int[count]; |
| if (has(CASE_INSENSITIVE)) { |
| if (has(UNICODE_CASE)) { |
| for (int i = 0; i < count; i++) { |
| tmp[i] = Character.toLowerCase( |
| Character.toUpperCase(buf[i])); |
| } |
| return hasSupplementary? new SliceUS(tmp) : new SliceU(tmp); |
| } |
| for (int i = 0; i < count; i++) { |
| tmp[i] = ASCII.toLower(buf[i]); |
| } |
| return hasSupplementary? new SliceIS(tmp) : new SliceI(tmp); |
| } |
| for (int i = 0; i < count; i++) { |
| tmp[i] = buf[i]; |
| } |
| return hasSupplementary ? new SliceS(tmp) : new Slice(tmp); |
| } |
| */ |
| // END Android-removed: Reimplement matching logic via ICU4C. |
| |
| // BEGIN Android-changed: reimplement matching logic natively via ICU. |
| // Use native implementation instead of > 3000 lines of helper methods. |
| private void compile() throws PatternSyntaxException { |
| if (pattern == null) { |
| throw new NullPointerException("pattern == null"); |
| } |
| |
| String icuPattern = pattern; |
| if ((flags & LITERAL) != 0) { |
| icuPattern = quote(pattern); |
| } |
| |
| // These are the flags natively supported by ICU. |
| // They even have the same value in native code. |
| int icuFlags = flags & (CASE_INSENSITIVE | COMMENTS | MULTILINE | DOTALL | UNIX_LINES); |
| nativePattern = PatternNative.create(icuPattern, icuFlags); |
| } |
| // END Android-changed: reimplement matching logic natively via ICU. |
| |
| // BEGIN Android-removed: Reimplement matching logic via ICU4C. |
| /** |
| * Node to anchor at the beginning of input. This object implements the |
| * match for a \A sequence, and the caret anchor will use this if not in |
| * multiline mode. |
| * |
| static final class Begin extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int fromIndex = (matcher.anchoringBounds) ? |
| matcher.from : 0; |
| if (i == fromIndex && next.match(matcher, i, seq)) { |
| matcher.first = i; |
| matcher.groups[0] = i; |
| matcher.groups[1] = matcher.last; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| } |
| |
| /** |
| * Node to anchor at the end of input. This is the absolute end, so this |
| * should not match at the last newline before the end as $ will. |
| * |
| static final class End extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int endIndex = (matcher.anchoringBounds) ? |
| matcher.to : matcher.getTextLength(); |
| if (i == endIndex) { |
| matcher.hitEnd = true; |
| return next.match(matcher, i, seq); |
| } |
| return false; |
| } |
| } |
| |
| /** |
| * Node to anchor at the beginning of a line. This is essentially the |
| * object to match for the multiline ^. |
| * |
| static final class Caret extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int startIndex = matcher.from; |
| int endIndex = matcher.to; |
| if (!matcher.anchoringBounds) { |
| startIndex = 0; |
| endIndex = matcher.getTextLength(); |
| } |
| // Perl does not match ^ at end of input even after newline |
| if (i == endIndex) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| if (i > startIndex) { |
| char ch = seq.charAt(i-1); |
| if (ch != '\n' && ch != '\r' |
| && (ch|1) != '\u2029' |
| && ch != '\u0085' ) { |
| return false; |
| } |
| // Should treat /r/n as one newline |
| if (ch == '\r' && seq.charAt(i) == '\n') |
| return false; |
| } |
| return next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Node to anchor at the beginning of a line when in unixdot mode. |
| * |
| static final class UnixCaret extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int startIndex = matcher.from; |
| int endIndex = matcher.to; |
| if (!matcher.anchoringBounds) { |
| startIndex = 0; |
| endIndex = matcher.getTextLength(); |
| } |
| // Perl does not match ^ at end of input even after newline |
| if (i == endIndex) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| if (i > startIndex) { |
| char ch = seq.charAt(i-1); |
| if (ch != '\n') { |
| return false; |
| } |
| } |
| return next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Node to match the location where the last match ended. |
| * This is used for the \G construct. |
| * |
| static final class LastMatch extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (i != matcher.oldLast) |
| return false; |
| return next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Node to anchor at the end of a line or the end of input based on the |
| * multiline mode. |
| * |
| * When not in multiline mode, the $ can only match at the very end |
| * of the input, unless the input ends in a line terminator in which |
| * it matches right before the last line terminator. |
| * |
| * Note that \r\n is considered an atomic line terminator. |
| * |
| * Like ^ the $ operator matches at a position, it does not match the |
| * line terminators themselves. |
| * |
| static final class Dollar extends Node { |
| boolean multiline; |
| Dollar(boolean mul) { |
| multiline = mul; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int endIndex = (matcher.anchoringBounds) ? |
| matcher.to : matcher.getTextLength(); |
| if (!multiline) { |
| if (i < endIndex - 2) |
| return false; |
| if (i == endIndex - 2) { |
| char ch = seq.charAt(i); |
| if (ch != '\r') |
| return false; |
| ch = seq.charAt(i + 1); |
| if (ch != '\n') |
| return false; |
| } |
| } |
| // Matches before any line terminator; also matches at the |
| // end of input |
| // Before line terminator: |
| // If multiline, we match here no matter what |
| // If not multiline, fall through so that the end |
| // is marked as hit; this must be a /r/n or a /n |
| // at the very end so the end was hit; more input |
| // could make this not match here |
| if (i < endIndex) { |
| char ch = seq.charAt(i); |
| if (ch == '\n') { |
| // No match between \r\n |
| if (i > 0 && seq.charAt(i-1) == '\r') |
| return false; |
| if (multiline) |
| return next.match(matcher, i, seq); |
| } else if (ch == '\r' || ch == '\u0085' || |
| (ch|1) == '\u2029') { |
| if (multiline) |
| return next.match(matcher, i, seq); |
| } else { // No line terminator, no match |
| return false; |
| } |
| } |
| // Matched at current end so hit end |
| matcher.hitEnd = true; |
| // If a $ matches because of end of input, then more input |
| // could cause it to fail! |
| matcher.requireEnd = true; |
| return next.match(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| next.study(info); |
| return info.deterministic; |
| } |
| } |
| |
| /** |
| * Node to anchor at the end of a line or the end of input based on the |
| * multiline mode when in unix lines mode. |
| * |
| static final class UnixDollar extends Node { |
| boolean multiline; |
| UnixDollar(boolean mul) { |
| multiline = mul; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int endIndex = (matcher.anchoringBounds) ? |
| matcher.to : matcher.getTextLength(); |
| if (i < endIndex) { |
| char ch = seq.charAt(i); |
| if (ch == '\n') { |
| // If not multiline, then only possible to |
| // match at very end or one before end |
| if (multiline == false && i != endIndex - 1) |
| return false; |
| // If multiline return next.match without setting |
| // matcher.hitEnd |
| if (multiline) |
| return next.match(matcher, i, seq); |
| } else { |
| return false; |
| } |
| } |
| // Matching because at the end or 1 before the end; |
| // more input could change this so set hitEnd |
| matcher.hitEnd = true; |
| // If a $ matches because of end of input, then more input |
| // could cause it to fail! |
| matcher.requireEnd = true; |
| return next.match(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| next.study(info); |
| return info.deterministic; |
| } |
| } |
| |
| /** |
| * Node class that matches a Unicode line ending '\R' |
| * |
| static final class LineEnding extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| // (u+000Du+000A|[u+000Au+000Bu+000Cu+000Du+0085u+2028u+2029]) |
| if (i < matcher.to) { |
| int ch = seq.charAt(i); |
| if (ch == 0x0A || ch == 0x0B || ch == 0x0C || |
| ch == 0x85 || ch == 0x2028 || ch == 0x2029) |
| return next.match(matcher, i + 1, seq); |
| if (ch == 0x0D) { |
| i++; |
| if (i < matcher.to) { |
| if (seq.charAt(i) == 0x0A && |
| next.match(matcher, i + 1, seq)) { |
| return true; |
| } |
| } else { |
| matcher.hitEnd = true; |
| } |
| return next.match(matcher, i, seq); |
| } |
| } else { |
| matcher.hitEnd = true; |
| } |
| return false; |
| } |
| boolean study(TreeInfo info) { |
| info.minLength++; |
| info.maxLength += 2; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Abstract node class to match one character satisfying some |
| * boolean property. |
| * |
| static class CharProperty extends Node { |
| final CharPredicate predicate; |
| |
| CharProperty (CharPredicate predicate) { |
| this.predicate = predicate; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (i < matcher.to) { |
| int ch = Character.codePointAt(seq, i); |
| i += Character.charCount(ch); |
| if (i <= matcher.to) { |
| return predicate.is(ch) && |
| next.match(matcher, i, seq); |
| } |
| } |
| matcher.hitEnd = true; |
| return false; |
| } |
| boolean study(TreeInfo info) { |
| info.minLength++; |
| info.maxLength++; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Optimized version of CharProperty that works only for |
| * properties never satisfied by Supplementary characters. |
| * |
| private static class BmpCharProperty extends CharProperty { |
| BmpCharProperty (BmpCharPredicate predicate) { |
| super(predicate); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (i < matcher.to) { |
| return predicate.is(seq.charAt(i)) && |
| next.match(matcher, i + 1, seq); |
| } else { |
| matcher.hitEnd = true; |
| return false; |
| } |
| } |
| } |
| |
| private static class NFCCharProperty extends Node { |
| CharPredicate predicate; |
| NFCCharProperty (CharPredicate predicate) { |
| this.predicate = predicate; |
| } |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (i < matcher.to) { |
| int ch0 = Character.codePointAt(seq, i); |
| int n = Character.charCount(ch0); |
| int j = Grapheme.nextBoundary(seq, i, matcher.to); |
| if (i + n == j) { // single cp grapheme, assume nfc |
| if (predicate.is(ch0)) |
| return next.match(matcher, j, seq); |
| } else { |
| while (i + n < j) { |
| String nfc = Normalizer.normalize( |
| seq.toString().substring(i, j), Normalizer.Form.NFC); |
| if (nfc.codePointCount(0, nfc.length()) == 1) { |
| if (predicate.is(nfc.codePointAt(0)) && |
| next.match(matcher, j, seq)) { |
| return true; |
| } |
| } |
| |
| ch0 = Character.codePointBefore(seq, j); |
| j -= Character.charCount(ch0); |
| } |
| } |
| if (j < matcher.to) |
| return false; |
| } |
| matcher.hitEnd = true; |
| return false; |
| } |
| |
| boolean study(TreeInfo info) { |
| info.minLength++; |
| info.deterministic = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Node class that matches an unicode extended grapheme cluster |
| * |
| static class XGrapheme extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (i < matcher.to) { |
| i = Grapheme.nextBoundary(seq, i, matcher.to); |
| return next.match(matcher, i, seq); |
| } |
| matcher.hitEnd = true; |
| return false; |
| } |
| |
| boolean study(TreeInfo info) { |
| info.minLength++; |
| info.deterministic = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Node class that handles grapheme boundaries |
| * |
| static class GraphemeBound extends Node { |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int startIndex = matcher.from; |
| int endIndex = matcher.to; |
| if (matcher.transparentBounds) { |
| startIndex = 0; |
| endIndex = matcher.getTextLength(); |
| } |
| if (i == startIndex) { |
| // continue with return below |
| } else if (i < endIndex) { |
| if (Character.isSurrogatePair(seq.charAt(i - 1), seq.charAt(i))) { |
| return false; |
| } |
| if (Grapheme.nextBoundary(seq, matcher.last, endIndex) > i) { |
| return false; |
| } |
| } else { |
| matcher.hitEnd = true; |
| matcher.requireEnd = true; |
| } |
| return next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Base class for all Slice nodes |
| * |
| static class SliceNode extends Node { |
| int[] buffer; |
| SliceNode(int[] buf) { |
| buffer = buf; |
| } |
| boolean study(TreeInfo info) { |
| info.minLength += buffer.length; |
| info.maxLength += buffer.length; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Node class for a case sensitive/BMP-only sequence of literal |
| * characters. |
| * |
| static class Slice extends SliceNode { |
| Slice(int[] buf) { |
| super(buf); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] buf = buffer; |
| int len = buf.length; |
| for (int j=0; j<len; j++) { |
| if ((i+j) >= matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| if (buf[j] != seq.charAt(i+j)) |
| return false; |
| } |
| return next.match(matcher, i+len, seq); |
| } |
| } |
| |
| /** |
| * Node class for a case_insensitive/BMP-only sequence of literal |
| * characters. |
| * |
| static class SliceI extends SliceNode { |
| SliceI(int[] buf) { |
| super(buf); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] buf = buffer; |
| int len = buf.length; |
| for (int j=0; j<len; j++) { |
| if ((i+j) >= matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| int c = seq.charAt(i+j); |
| if (buf[j] != c && |
| buf[j] != ASCII.toLower(c)) |
| return false; |
| } |
| return next.match(matcher, i+len, seq); |
| } |
| } |
| |
| /** |
| * Node class for a unicode_case_insensitive/BMP-only sequence of |
| * literal characters. Uses unicode case folding. |
| * |
| static final class SliceU extends SliceNode { |
| SliceU(int[] buf) { |
| super(buf); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] buf = buffer; |
| int len = buf.length; |
| for (int j=0; j<len; j++) { |
| if ((i+j) >= matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| int c = seq.charAt(i+j); |
| if (buf[j] != c && |
| buf[j] != Character.toLowerCase(Character.toUpperCase(c))) |
| return false; |
| } |
| return next.match(matcher, i+len, seq); |
| } |
| } |
| |
| /** |
| * Node class for a case sensitive sequence of literal characters |
| * including supplementary characters. |
| * |
| static final class SliceS extends Slice { |
| SliceS(int[] buf) { |
| super(buf); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] buf = buffer; |
| int x = i; |
| for (int j = 0; j < buf.length; j++) { |
| if (x >= matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| int c = Character.codePointAt(seq, x); |
| if (buf[j] != c) |
| return false; |
| x += Character.charCount(c); |
| if (x > matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| } |
| return next.match(matcher, x, seq); |
| } |
| } |
| |
| /** |
| * Node class for a case insensitive sequence of literal characters |
| * including supplementary characters. |
| * |
| static class SliceIS extends SliceNode { |
| SliceIS(int[] buf) { |
| super(buf); |
| } |
| int toLower(int c) { |
| return ASCII.toLower(c); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] buf = buffer; |
| int x = i; |
| for (int j = 0; j < buf.length; j++) { |
| if (x >= matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| int c = Character.codePointAt(seq, x); |
| if (buf[j] != c && buf[j] != toLower(c)) |
| return false; |
| x += Character.charCount(c); |
| if (x > matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| } |
| return next.match(matcher, x, seq); |
| } |
| } |
| |
| /** |
| * Node class for a case insensitive sequence of literal characters. |
| * Uses unicode case folding. |
| * |
| static final class SliceUS extends SliceIS { |
| SliceUS(int[] buf) { |
| super(buf); |
| } |
| int toLower(int c) { |
| return Character.toLowerCase(Character.toUpperCase(c)); |
| } |
| } |
| |
| /** |
| * The 0 or 1 quantifier. This one class implements all three types. |
| * |
| static final class Ques extends Node { |
| Node atom; |
| Qtype type; |
| Ques(Node node, Qtype type) { |
| this.atom = node; |
| this.type = type; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| switch (type) { |
| case GREEDY: |
| return (atom.match(matcher, i, seq) && next.match(matcher, matcher.last, seq)) |
| || next.match(matcher, i, seq); |
| case LAZY: |
| return next.match(matcher, i, seq) |
| || (atom.match(matcher, i, seq) && next.match(matcher, matcher.last, seq)); |
| case POSSESSIVE: |
| if (atom.match(matcher, i, seq)) i = matcher.last; |
| return next.match(matcher, i, seq); |
| default: |
| return atom.match(matcher, i, seq) && next.match(matcher, matcher.last, seq); |
| } |
| } |
| boolean study(TreeInfo info) { |
| if (type != Qtype.INDEPENDENT) { |
| int minL = info.minLength; |
| atom.study(info); |
| info.minLength = minL; |
| info.deterministic = false; |
| return next.study(info); |
| } else { |
| atom.study(info); |
| return next.study(info); |
| } |
| } |
| } |
| |
| /** |
| * Handles the greedy style repetition with the specified minimum |
| * and the maximum equal to MAX_REPS, for *, + and {N,} quantifiers. |
| * |
| static class CharPropertyGreedy extends Node { |
| final CharPredicate predicate; |
| final int cmin; |
| |
| CharPropertyGreedy(CharProperty cp, int cmin) { |
| this.predicate = cp.predicate; |
| this.cmin = cmin; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int starti = i; |
| int n = 0; |
| int to = matcher.to; |
| // greedy, all the way down |
| while (i < to) { |
| int ch = Character.codePointAt(seq, i); |
| int len = Character.charCount(ch); |
| if (i + len > to) { |
| // the region cut off the high half of a surrogate pair |
| matcher.hitEnd = true; |
| ch = seq.charAt(i); |
| len = 1; |
| } |
| if (!predicate.is(ch)) |
| break; |
| i += len; |
| n++; |
| } |
| if (i >= to) { |
| matcher.hitEnd = true; |
| } |
| while (n >= cmin) { |
| if (next.match(matcher, i, seq)) |
| return true; |
| if (n == cmin) |
| return false; |
| // backing off if match fails |
| int ch = Character.codePointBefore(seq, i); |
| // check if the region cut off the low half of a surrogate pair |
| i = Math.max(starti, i - Character.charCount(ch)); |
| n--; |
| } |
| return false; |
| } |
| |
| boolean study(TreeInfo info) { |
| info.minLength += cmin; |
| if (info.maxValid) { |
| info.maxLength += MAX_REPS; |
| } |
| info.deterministic = false; |
| return next.study(info); |
| } |
| } |
| |
| static final class BmpCharPropertyGreedy extends CharPropertyGreedy { |
| |
| BmpCharPropertyGreedy(BmpCharProperty bcp, int cmin) { |
| super(bcp, cmin); |
| } |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int n = 0; |
| int to = matcher.to; |
| while (i < to && predicate.is(seq.charAt(i))) { |
| i++; n++; |
| } |
| if (i >= to) { |
| matcher.hitEnd = true; |
| } |
| while (n >= cmin) { |
| if (next.match(matcher, i, seq)) |
| return true; |
| i--; n--; // backing off if match fails |
| } |
| return false; |
| } |
| } |
| |
| /** |
| * Handles the curly-brace style repetition with a specified minimum and |
| * maximum occurrences. The * quantifier is handled as a special case. |
| * This class handles the three types. |
| * |
| static final class Curly extends Node { |
| Node atom; |
| Qtype type; |
| int cmin; |
| int cmax; |
| |
| Curly(Node node, int cmin, int cmax, Qtype type) { |
| this.atom = node; |
| this.type = type; |
| this.cmin = cmin; |
| this.cmax = cmax; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int j; |
| for (j = 0; j < cmin; j++) { |
| if (atom.match(matcher, i, seq)) { |
| i = matcher.last; |
| continue; |
| } |
| return false; |
| } |
| if (type == Qtype.GREEDY) |
| return match0(matcher, i, j, seq); |
| else if (type == Qtype.LAZY) |
| return match1(matcher, i, j, seq); |
| else |
| return match2(matcher, i, j, seq); |
| } |
| // Greedy match. |
| // i is the index to start matching at |
| // j is the number of atoms that have matched |
| boolean match0(Matcher matcher, int i, int j, CharSequence seq) { |
| if (j >= cmax) { |
| // We have matched the maximum... continue with the rest of |
| // the regular expression |
| return next.match(matcher, i, seq); |
| } |
| int backLimit = j; |
| while (atom.match(matcher, i, seq)) { |
| // k is the length of this match |
| int k = matcher.last - i; |
| if (k == 0) // Zero length match |
| break; |
| // Move up index and number matched |
| i = matcher.last; |
| j++; |
| // We are greedy so match as many as we can |
| while (j < cmax) { |
| if (!atom.match(matcher, i, seq)) |
| break; |
| if (i + k != matcher.last) { |
| if (match0(matcher, matcher.last, j+1, seq)) |
| return true; |
| break; |
| } |
| i += k; |
| j++; |
| } |
| // Handle backing off if match fails |
| while (j >= backLimit) { |
| if (next.match(matcher, i, seq)) |
| return true; |
| i -= k; |
| j--; |
| } |
| return false; |
| } |
| return next.match(matcher, i, seq); |
| } |
| // Reluctant match. At this point, the minimum has been satisfied. |
| // i is the index to start matching at |
| // j is the number of atoms that have matched |
| boolean match1(Matcher matcher, int i, int j, CharSequence seq) { |
| for (;;) { |
| // Try finishing match without consuming any more |
| if (next.match(matcher, i, seq)) |
| return true; |
| // At the maximum, no match found |
| if (j >= cmax) |
| return false; |
| // Okay, must try one more atom |
| if (!atom.match(matcher, i, seq)) |
| return false; |
| // If we haven't moved forward then must break out |
| if (i == matcher.last) |
| return false; |
| // Move up index and number matched |
| i = matcher.last; |
| j++; |
| } |
| } |
| boolean match2(Matcher matcher, int i, int j, CharSequence seq) { |
| for (; j < cmax; j++) { |
| if (!atom.match(matcher, i, seq)) |
| break; |
| if (i == matcher.last) |
| break; |
| i = matcher.last; |
| } |
| return next.match(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| // Save original info |
| int minL = info.minLength; |
| int maxL = info.maxLength; |
| boolean maxV = info.maxValid; |
| boolean detm = info.deterministic; |
| info.reset(); |
| |
| atom.study(info); |
| |
| int temp = info.minLength * cmin + minL; |
| if (temp < minL) { |
| temp = 0xFFFFFFF; // arbitrary large number |
| } |
| info.minLength = temp; |
| |
| if (maxV & info.maxValid) { |
| temp = info.maxLength * cmax + maxL; |
| info.maxLength = temp; |
| if (temp < maxL) { |
| info.maxValid = false; |
| } |
| } else { |
| info.maxValid = false; |
| } |
| |
| if (info.deterministic && cmin == cmax) |
| info.deterministic = detm; |
| else |
| info.deterministic = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Handles the curly-brace style repetition with a specified minimum and |
| * maximum occurrences in deterministic cases. This is an iterative |
| * optimization over the Prolog and Loop system which would handle this |
| * in a recursive way. The * quantifier is handled as a special case. |
| * If capture is true then this class saves group settings and ensures |
| * that groups are unset when backing off of a group match. |
| * |
| static final class GroupCurly extends Node { |
| Node atom; |
| Qtype type; |
| int cmin; |
| int cmax; |
| int localIndex; |
| int groupIndex; |
| boolean capture; |
| |
| GroupCurly(Node node, int cmin, int cmax, Qtype type, int local, |
| int group, boolean capture) { |
| this.atom = node; |
| this.type = type; |
| this.cmin = cmin; |
| this.cmax = cmax; |
| this.localIndex = local; |
| this.groupIndex = group; |
| this.capture = capture; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] groups = matcher.groups; |
| int[] locals = matcher.locals; |
| int save0 = locals[localIndex]; |
| int save1 = 0; |
| int save2 = 0; |
| |
| if (capture) { |
| save1 = groups[groupIndex]; |
| save2 = groups[groupIndex+1]; |
| } |
| |
| // Notify GroupTail there is no need to setup group info |
| // because it will be set here |
| locals[localIndex] = -1; |
| |
| boolean ret = true; |
| for (int j = 0; j < cmin; j++) { |
| if (atom.match(matcher, i, seq)) { |
| if (capture) { |
| groups[groupIndex] = i; |
| groups[groupIndex+1] = matcher.last; |
| } |
| i = matcher.last; |
| } else { |
| ret = false; |
| break; |
| } |
| } |
| if (ret) { |
| if (type == Qtype.GREEDY) { |
| ret = match0(matcher, i, cmin, seq); |
| } else if (type == Qtype.LAZY) { |
| ret = match1(matcher, i, cmin, seq); |
| } else { |
| ret = match2(matcher, i, cmin, seq); |
| } |
| } |
| if (!ret) { |
| locals[localIndex] = save0; |
| if (capture) { |
| groups[groupIndex] = save1; |
| groups[groupIndex+1] = save2; |
| } |
| } |
| return ret; |
| } |
| // Aggressive group match |
| boolean match0(Matcher matcher, int i, int j, CharSequence seq) { |
| // don't back off passing the starting "j" |
| int min = j; |
| int[] groups = matcher.groups; |
| int save0 = 0; |
| int save1 = 0; |
| if (capture) { |
| save0 = groups[groupIndex]; |
| save1 = groups[groupIndex+1]; |
| } |
| for (;;) { |
| if (j >= cmax) |
| break; |
| if (!atom.match(matcher, i, seq)) |
| break; |
| int k = matcher.last - i; |
| if (k <= 0) { |
| if (capture) { |
| groups[groupIndex] = i; |
| groups[groupIndex+1] = i + k; |
| } |
| i = i + k; |
| break; |
| } |
| for (;;) { |
| if (capture) { |
| groups[groupIndex] = i; |
| groups[groupIndex+1] = i + k; |
| } |
| i = i + k; |
| if (++j >= cmax) |
| break; |
| if (!atom.match(matcher, i, seq)) |
| break; |
| if (i + k != matcher.last) { |
| if (match0(matcher, i, j, seq)) |
| return true; |
| break; |
| } |
| } |
| while (j > min) { |
| if (next.match(matcher, i, seq)) { |
| if (capture) { |
| groups[groupIndex+1] = i; |
| groups[groupIndex] = i - k; |
| } |
| return true; |
| } |
| // backing off |
| i = i - k; |
| if (capture) { |
| groups[groupIndex+1] = i; |
| groups[groupIndex] = i - k; |
| } |
| j--; |
| |
| } |
| break; |
| } |
| if (capture) { |
| groups[groupIndex] = save0; |
| groups[groupIndex+1] = save1; |
| } |
| return next.match(matcher, i, seq); |
| } |
| // Reluctant matching |
| boolean match1(Matcher matcher, int i, int j, CharSequence seq) { |
| for (;;) { |
| if (next.match(matcher, i, seq)) |
| return true; |
| if (j >= cmax) |
| return false; |
| if (!atom.match(matcher, i, seq)) |
| return false; |
| if (i == matcher.last) |
| return false; |
| if (capture) { |
| matcher.groups[groupIndex] = i; |
| matcher.groups[groupIndex+1] = matcher.last; |
| } |
| i = matcher.last; |
| j++; |
| } |
| } |
| // Possessive matching |
| boolean match2(Matcher matcher, int i, int j, CharSequence seq) { |
| for (; j < cmax; j++) { |
| if (!atom.match(matcher, i, seq)) { |
| break; |
| } |
| if (capture) { |
| matcher.groups[groupIndex] = i; |
| matcher.groups[groupIndex+1] = matcher.last; |
| } |
| if (i == matcher.last) { |
| break; |
| } |
| i = matcher.last; |
| } |
| return next.match(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| // Save original info |
| int minL = info.minLength; |
| int maxL = info.maxLength; |
| boolean maxV = info.maxValid; |
| boolean detm = info.deterministic; |
| info.reset(); |
| |
| atom.study(info); |
| |
| int temp = info.minLength * cmin + minL; |
| if (temp < minL) { |
| temp = 0xFFFFFFF; // Arbitrary large number |
| } |
| info.minLength = temp; |
| |
| if (maxV & info.maxValid) { |
| temp = info.maxLength * cmax + maxL; |
| info.maxLength = temp; |
| if (temp < maxL) { |
| info.maxValid = false; |
| } |
| } else { |
| info.maxValid = false; |
| } |
| |
| if (info.deterministic && cmin == cmax) { |
| info.deterministic = detm; |
| } else { |
| info.deterministic = false; |
| } |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * A Guard node at the end of each atom node in a Branch. It |
| * serves the purpose of chaining the "match" operation to |
| * "next" but not the "study", so we can collect the TreeInfo |
| * of each atom node without including the TreeInfo of the |
| * "next". |
| * |
| static final class BranchConn extends Node { |
| BranchConn() {} |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| return next.match(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| return info.deterministic; |
| } |
| } |
| |
| /** |
| * Handles the branching of alternations. Note this is also used for |
| * the ? quantifier to branch between the case where it matches once |
| * and where it does not occur. |
| * |
| static final class Branch extends Node { |
| Node[] atoms = new Node[2]; |
| int size = 2; |
| Node conn; |
| Branch(Node first, Node second, Node branchConn) { |
| conn = branchConn; |
| atoms[0] = first; |
| atoms[1] = second; |
| } |
| |
| void add(Node node) { |
| if (size >= atoms.length) { |
| Node[] tmp = new Node[atoms.length*2]; |
| System.arraycopy(atoms, 0, tmp, 0, atoms.length); |
| atoms = tmp; |
| } |
| atoms[size++] = node; |
| } |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| for (int n = 0; n < size; n++) { |
| if (atoms[n] == null) { |
| if (conn.next.match(matcher, i, seq)) |
| return true; |
| } else if (atoms[n].match(matcher, i, seq)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| boolean study(TreeInfo info) { |
| int minL = info.minLength; |
| int maxL = info.maxLength; |
| boolean maxV = info.maxValid; |
| |
| int minL2 = Integer.MAX_VALUE; //arbitrary large enough num |
| int maxL2 = -1; |
| for (int n = 0; n < size; n++) { |
| info.reset(); |
| if (atoms[n] != null) |
| atoms[n].study(info); |
| minL2 = Math.min(minL2, info.minLength); |
| maxL2 = Math.max(maxL2, info.maxLength); |
| maxV = (maxV & info.maxValid); |
| } |
| |
| minL += minL2; |
| maxL += maxL2; |
| |
| info.reset(); |
| conn.next.study(info); |
| |
| info.minLength += minL; |
| info.maxLength += maxL; |
| info.maxValid &= maxV; |
| info.deterministic = false; |
| return false; |
| } |
| } |
| |
| /** |
| * The GroupHead saves the location where the group begins in the locals |
| * and restores them when the match is done. |
| * |
| * The matchRef is used when a reference to this group is accessed later |
| * in the expression. The locals will have a negative value in them to |
| * indicate that we do not want to unset the group if the reference |
| * doesn't match. |
| * |
| static final class GroupHead extends Node { |
| int localIndex; |
| GroupTail tail; // for debug/print only, match does not need to know |
| GroupHead(int localCount) { |
| localIndex = localCount; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int save = matcher.locals[localIndex]; |
| matcher.locals[localIndex] = i; |
| boolean ret = next.match(matcher, i, seq); |
| matcher.locals[localIndex] = save; |
| return ret; |
| } |
| } |
| |
| /** |
| * The GroupTail handles the setting of group beginning and ending |
| * locations when groups are successfully matched. It must also be able to |
| * unset groups that have to be backed off of. |
| * |
| * The GroupTail node is also used when a previous group is referenced, |
| * and in that case no group information needs to be set. |
| * |
| static final class GroupTail extends Node { |
| int localIndex; |
| int groupIndex; |
| GroupTail(int localCount, int groupCount) { |
| localIndex = localCount; |
| groupIndex = groupCount + groupCount; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int tmp = matcher.locals[localIndex]; |
| if (tmp >= 0) { // This is the normal group case. |
| // Save the group so we can unset it if it |
| // backs off of a match. |
| int groupStart = matcher.groups[groupIndex]; |
| int groupEnd = matcher.groups[groupIndex+1]; |
| |
| matcher.groups[groupIndex] = tmp; |
| matcher.groups[groupIndex+1] = i; |
| if (next.match(matcher, i, seq)) { |
| return true; |
| } |
| matcher.groups[groupIndex] = groupStart; |
| matcher.groups[groupIndex+1] = groupEnd; |
| return false; |
| } else { |
| // This is a group reference case. We don't need to save any |
| // group info because it isn't really a group. |
| matcher.last = i; |
| return true; |
| } |
| } |
| } |
| |
| /** |
| * This sets up a loop to handle a recursive quantifier structure. |
| * |
| static final class Prolog extends Node { |
| Loop loop; |
| Prolog(Loop loop) { |
| this.loop = loop; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| return loop.matchInit(matcher, i, seq); |
| } |
| boolean study(TreeInfo info) { |
| return loop.study(info); |
| } |
| } |
| |
| /** |
| * Handles the repetition count for a greedy Curly. The matchInit |
| * is called from the Prolog to save the index of where the group |
| * beginning is stored. A zero length group check occurs in the |
| * normal match but is skipped in the matchInit. |
| * |
| static class Loop extends Node { |
| Node body; |
| int countIndex; // local count index in matcher locals |
| int beginIndex; // group beginning index |
| int cmin, cmax; |
| int posIndex; |
| Loop(int countIndex, int beginIndex) { |
| this.countIndex = countIndex; |
| this.beginIndex = beginIndex; |
| this.posIndex = -1; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| // Avoid infinite loop in zero-length case. |
| if (i > matcher.locals[beginIndex]) { |
| int count = matcher.locals[countIndex]; |
| |
| // This block is for before we reach the minimum |
| // iterations required for the loop to match |
| if (count < cmin) { |
| matcher.locals[countIndex] = count + 1; |
| boolean b = body.match(matcher, i, seq); |
| // If match failed we must backtrack, so |
| // the loop count should NOT be incremented |
| if (!b) |
| matcher.locals[countIndex] = count; |
| // Return success or failure since we are under |
| // minimum |
| return b; |
| } |
| // This block is for after we have the minimum |
| // iterations required for the loop to match |
| if (count < cmax) { |
| // Let's check if we have already tried and failed |
| // at this starting position "i" in the past. |
| // If yes, then just return false wihtout trying |
| // again, to stop the exponential backtracking. |
| if (posIndex != -1 && |
| matcher.localsPos[posIndex].contains(i)) { |
| return next.match(matcher, i, seq); |
| } |
| matcher.locals[countIndex] = count + 1; |
| boolean b = body.match(matcher, i, seq); |
| // If match failed we must backtrack, so |
| // the loop count should NOT be incremented |
| if (b) |
| return true; |
| matcher.locals[countIndex] = count; |
| // save the failed position |
| if (posIndex != -1) { |
| matcher.localsPos[posIndex].add(i); |
| } |
| } |
| } |
| return next.match(matcher, i, seq); |
| } |
| boolean matchInit(Matcher matcher, int i, CharSequence seq) { |
| int save = matcher.locals[countIndex]; |
| boolean ret; |
| if (posIndex != -1 && matcher.localsPos[posIndex] == null) { |
| matcher.localsPos[posIndex] = new IntHashSet(); |
| } |
| if (0 < cmin) { |
| matcher.locals[countIndex] = 1; |
| ret = body.match(matcher, i, seq); |
| } else if (0 < cmax) { |
| matcher.locals[countIndex] = 1; |
| ret = body.match(matcher, i, seq); |
| if (ret == false) |
| ret = next.match(matcher, i, seq); |
| } else { |
| ret = next.match(matcher, i, seq); |
| } |
| matcher.locals[countIndex] = save; |
| return ret; |
| } |
| boolean study(TreeInfo info) { |
| info.maxValid = false; |
| info.deterministic = false; |
| return false; |
| } |
| } |
| |
| /** |
| * Handles the repetition count for a reluctant Curly. The matchInit |
| * is called from the Prolog to save the index of where the group |
| * beginning is stored. A zero length group check occurs in the |
| * normal match but is skipped in the matchInit. |
| * |
| static final class LazyLoop extends Loop { |
| LazyLoop(int countIndex, int beginIndex) { |
| super(countIndex, beginIndex); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| // Check for zero length group |
| if (i > matcher.locals[beginIndex]) { |
| int count = matcher.locals[countIndex]; |
| if (count < cmin) { |
| matcher.locals[countIndex] = count + 1; |
| boolean result = body.match(matcher, i, seq); |
| // If match failed we must backtrack, so |
| // the loop count should NOT be incremented |
| if (!result) |
| matcher.locals[countIndex] = count; |
| return result; |
| } |
| if (next.match(matcher, i, seq)) |
| return true; |
| if (count < cmax) { |
| matcher.locals[countIndex] = count + 1; |
| boolean result = body.match(matcher, i, seq); |
| // If match failed we must backtrack, so |
| // the loop count should NOT be incremented |
| if (!result) |
| matcher.locals[countIndex] = count; |
| return result; |
| } |
| return false; |
| } |
| return next.match(matcher, i, seq); |
| } |
| boolean matchInit(Matcher matcher, int i, CharSequence seq) { |
| int save = matcher.locals[countIndex]; |
| boolean ret = false; |
| if (0 < cmin) { |
| matcher.locals[countIndex] = 1; |
| ret = body.match(matcher, i, seq); |
| } else if (next.match(matcher, i, seq)) { |
| ret = true; |
| } else if (0 < cmax) { |
| matcher.locals[countIndex] = 1; |
| ret = body.match(matcher, i, seq); |
| } |
| matcher.locals[countIndex] = save; |
| return ret; |
| } |
| boolean study(TreeInfo info) { |
| info.maxValid = false; |
| info.deterministic = false; |
| return false; |
| } |
| } |
| |
| /** |
| * Refers to a group in the regular expression. Attempts to match |
| * whatever the group referred to last matched. |
| * |
| static class BackRef extends Node { |
| int groupIndex; |
| BackRef(int groupCount) { |
| super(); |
| groupIndex = groupCount + groupCount; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int j = matcher.groups[groupIndex]; |
| int k = matcher.groups[groupIndex+1]; |
| |
| int groupSize = k - j; |
| // If the referenced group didn't match, neither can this |
| if (j < 0) |
| return false; |
| |
| // If there isn't enough input left no match |
| if (i + groupSize > matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| // Check each new char to make sure it matches what the group |
| // referenced matched last time around |
| for (int index=0; index<groupSize; index++) |
| if (seq.charAt(i+index) != seq.charAt(j+index)) |
| return false; |
| |
| return next.match(matcher, i+groupSize, seq); |
| } |
| boolean study(TreeInfo info) { |
| info.maxValid = false; |
| return next.study(info); |
| } |
| } |
| |
| static class CIBackRef extends Node { |
| int groupIndex; |
| boolean doUnicodeCase; |
| CIBackRef(int groupCount, boolean doUnicodeCase) { |
| super(); |
| groupIndex = groupCount + groupCount; |
| this.doUnicodeCase = doUnicodeCase; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int j = matcher.groups[groupIndex]; |
| int k = matcher.groups[groupIndex+1]; |
| |
| int groupSize = k - j; |
| |
| // If the referenced group didn't match, neither can this |
| if (j < 0) |
| return false; |
| |
| // If there isn't enough input left no match |
| if (i + groupSize > matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| |
| // Check each new char to make sure it matches what the group |
| // referenced matched last time around |
| int x = i; |
| for (int index=0; index<groupSize; index++) { |
| int c1 = Character.codePointAt(seq, x); |
| int c2 = Character.codePointAt(seq, j); |
| if (c1 != c2) { |
| if (doUnicodeCase) { |
| int cc1 = Character.toUpperCase(c1); |
| int cc2 = Character.toUpperCase(c2); |
| if (cc1 != cc2 && |
| Character.toLowerCase(cc1) != |
| Character.toLowerCase(cc2)) |
| return false; |
| } else { |
| if (ASCII.toLower(c1) != ASCII.toLower(c2)) |
| return false; |
| } |
| } |
| x += Character.charCount(c1); |
| j += Character.charCount(c2); |
| } |
| |
| return next.match(matcher, i+groupSize, seq); |
| } |
| boolean study(TreeInfo info) { |
| info.maxValid = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Searches until the next instance of its atom. This is useful for |
| * finding the atom efficiently without passing an instance of it |
| * (greedy problem) and without a lot of wasted search time (reluctant |
| * problem). |
| * |
| static final class First extends Node { |
| Node atom; |
| First(Node node) { |
| this.atom = BnM.optimize(node); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| if (atom instanceof BnM) { |
| return atom.match(matcher, i, seq) |
| && next.match(matcher, matcher.last, seq); |
| } |
| for (;;) { |
| if (i > matcher.to) { |
| matcher.hitEnd = true; |
| return false; |
| } |
| if (atom.match(matcher, i, seq)) { |
| return next.match(matcher, matcher.last, seq); |
| } |
| i += countChars(seq, i, 1); |
| matcher.first++; |
| } |
| } |
| boolean study(TreeInfo info) { |
| atom.study(info); |
| info.maxValid = false; |
| info.deterministic = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Zero width positive lookahead. |
| * |
| static final class Pos extends Node { |
| Node cond; |
| Pos(Node cond) { |
| this.cond = cond; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int savedTo = matcher.to; |
| boolean conditionMatched; |
| |
| // Relax transparent region boundaries for lookahead |
| if (matcher.transparentBounds) |
| matcher.to = matcher.getTextLength(); |
| try { |
| conditionMatched = cond.match(matcher, i, seq); |
| } finally { |
| // Reinstate region boundaries |
| matcher.to = savedTo; |
| } |
| return conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Zero width negative lookahead. |
| * |
| static final class Neg extends Node { |
| Node cond; |
| Neg(Node cond) { |
| this.cond = cond; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int savedTo = matcher.to; |
| boolean conditionMatched; |
| |
| // Relax transparent region boundaries for lookahead |
| if (matcher.transparentBounds) |
| matcher.to = matcher.getTextLength(); |
| try { |
| if (i < matcher.to) { |
| conditionMatched = !cond.match(matcher, i, seq); |
| } else { |
| // If a negative lookahead succeeds then more input |
| // could cause it to fail! |
| matcher.requireEnd = true; |
| conditionMatched = !cond.match(matcher, i, seq); |
| } |
| } finally { |
| // Reinstate region boundaries |
| matcher.to = savedTo; |
| } |
| return conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * For use with lookbehinds; matches the position where the lookbehind |
| * was encountered. |
| * |
| static class LookBehindEndNode extends Node { |
| private LookBehindEndNode() {} // Singleton |
| |
| static LookBehindEndNode INSTANCE = new LookBehindEndNode(); |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| return i == matcher.lookbehindTo; |
| } |
| } |
| |
| /** |
| * Zero width positive lookbehind. |
| * |
| static class Behind extends Node { |
| Node cond; |
| int rmax, rmin; |
| Behind(Node cond, int rmax, int rmin) { |
| this.cond = cond; |
| this.rmax = rmax; |
| this.rmin = rmin; |
| } |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int savedFrom = matcher.from; |
| boolean conditionMatched = false; |
| int startIndex = (!matcher.transparentBounds) ? |
| matcher.from : 0; |
| int from = Math.max(i - rmax, startIndex); |
| // Set end boundary |
| int savedLBT = matcher.lookbehindTo; |
| matcher.lookbehindTo = i; |
| // Relax transparent region boundaries for lookbehind |
| if (matcher.transparentBounds) |
| matcher.from = 0; |
| for (int j = i - rmin; !conditionMatched && j >= from; j--) { |
| conditionMatched = cond.match(matcher, j, seq); |
| } |
| matcher.from = savedFrom; |
| matcher.lookbehindTo = savedLBT; |
| return conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Zero width positive lookbehind, including supplementary |
| * characters or unpaired surrogates. |
| * |
| static final class BehindS extends Behind { |
| BehindS(Node cond, int rmax, int rmin) { |
| super(cond, rmax, rmin); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int rmaxChars = countChars(seq, i, -rmax); |
| int rminChars = countChars(seq, i, -rmin); |
| int savedFrom = matcher.from; |
| int startIndex = (!matcher.transparentBounds) ? |
| matcher.from : 0; |
| boolean conditionMatched = false; |
| int from = Math.max(i - rmaxChars, startIndex); |
| // Set end boundary |
| int savedLBT = matcher.lookbehindTo; |
| matcher.lookbehindTo = i; |
| // Relax transparent region boundaries for lookbehind |
| if (matcher.transparentBounds) |
| matcher.from = 0; |
| |
| for (int j = i - rminChars; |
| !conditionMatched && j >= from; |
| j -= j>from ? countChars(seq, j, -1) : 1) { |
| conditionMatched = cond.match(matcher, j, seq); |
| } |
| matcher.from = savedFrom; |
| matcher.lookbehindTo = savedLBT; |
| return conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Zero width negative lookbehind. |
| * |
| static class NotBehind extends Node { |
| Node cond; |
| int rmax, rmin; |
| NotBehind(Node cond, int rmax, int rmin) { |
| this.cond = cond; |
| this.rmax = rmax; |
| this.rmin = rmin; |
| } |
| |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int savedLBT = matcher.lookbehindTo; |
| int savedFrom = matcher.from; |
| boolean conditionMatched = false; |
| int startIndex = (!matcher.transparentBounds) ? |
| matcher.from : 0; |
| int from = Math.max(i - rmax, startIndex); |
| matcher.lookbehindTo = i; |
| // Relax transparent region boundaries for lookbehind |
| if (matcher.transparentBounds) |
| matcher.from = 0; |
| for (int j = i - rmin; !conditionMatched && j >= from; j--) { |
| conditionMatched = cond.match(matcher, j, seq); |
| } |
| // Reinstate region boundaries |
| matcher.from = savedFrom; |
| matcher.lookbehindTo = savedLBT; |
| return !conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Zero width negative lookbehind, including supplementary |
| * characters or unpaired surrogates. |
| * |
| static final class NotBehindS extends NotBehind { |
| NotBehindS(Node cond, int rmax, int rmin) { |
| super(cond, rmax, rmin); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int rmaxChars = countChars(seq, i, -rmax); |
| int rminChars = countChars(seq, i, -rmin); |
| int savedFrom = matcher.from; |
| int savedLBT = matcher.lookbehindTo; |
| boolean conditionMatched = false; |
| int startIndex = (!matcher.transparentBounds) ? |
| matcher.from : 0; |
| int from = Math.max(i - rmaxChars, startIndex); |
| matcher.lookbehindTo = i; |
| // Relax transparent region boundaries for lookbehind |
| if (matcher.transparentBounds) |
| matcher.from = 0; |
| for (int j = i - rminChars; |
| !conditionMatched && j >= from; |
| j -= j>from ? countChars(seq, j, -1) : 1) { |
| conditionMatched = cond.match(matcher, j, seq); |
| } |
| //Reinstate region boundaries |
| matcher.from = savedFrom; |
| matcher.lookbehindTo = savedLBT; |
| return !conditionMatched && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Handles word boundaries. Includes a field to allow this one class to |
| * deal with the different types of word boundaries we can match. The word |
| * characters include underscores, letters, and digits. Non spacing marks |
| * can are also part of a word if they have a base character, otherwise |
| * they are ignored for purposes of finding word boundaries. |
| * |
| static final class Bound extends Node { |
| static int LEFT = 0x1; |
| static int RIGHT= 0x2; |
| static int BOTH = 0x3; |
| static int NONE = 0x4; |
| int type; |
| boolean useUWORD; |
| Bound(int n, boolean useUWORD) { |
| type = n; |
| this.useUWORD = useUWORD; |
| } |
| |
| boolean isWord(int ch) { |
| return useUWORD ? CharPredicates.WORD().is(ch) |
| : (ch == '_' || Character.isLetterOrDigit(ch)); |
| } |
| |
| int check(Matcher matcher, int i, CharSequence seq) { |
| int ch; |
| boolean left = false; |
| int startIndex = matcher.from; |
| int endIndex = matcher.to; |
| if (matcher.transparentBounds) { |
| startIndex = 0; |
| endIndex = matcher.getTextLength(); |
| } |
| if (i > startIndex) { |
| ch = Character.codePointBefore(seq, i); |
| left = (isWord(ch) || |
| ((Character.getType(ch) == Character.NON_SPACING_MARK) |
| && hasBaseCharacter(matcher, i-1, seq))); |
| } |
| boolean right = false; |
| if (i < endIndex) { |
| ch = Character.codePointAt(seq, i); |
| right = (isWord(ch) || |
| ((Character.getType(ch) == Character.NON_SPACING_MARK) |
| && hasBaseCharacter(matcher, i, seq))); |
| } else { |
| // Tried to access char past the end |
| matcher.hitEnd = true; |
| // The addition of another char could wreck a boundary |
| matcher.requireEnd = true; |
| } |
| return ((left ^ right) ? (right ? LEFT : RIGHT) : NONE); |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| return (check(matcher, i, seq) & type) > 0 |
| && next.match(matcher, i, seq); |
| } |
| } |
| |
| /** |
| * Non spacing marks only count as word characters in bounds calculations |
| * if they have a base character. |
| * |
| private static boolean hasBaseCharacter(Matcher matcher, int i, |
| CharSequence seq) |
| { |
| int start = (!matcher.transparentBounds) ? |
| matcher.from : 0; |
| for (int x=i; x >= start; x--) { |
| int ch = Character.codePointAt(seq, x); |
| if (Character.isLetterOrDigit(ch)) |
| return true; |
| if (Character.getType(ch) == Character.NON_SPACING_MARK) |
| continue; |
| return false; |
| } |
| return false; |
| } |
| |
| /** |
| * Attempts to match a slice in the input using the Boyer-Moore string |
| * matching algorithm. The algorithm is based on the idea that the |
| * pattern can be shifted farther ahead in the search text if it is |
| * matched right to left. |
| * <p> |
| * The pattern is compared to the input one character at a time, from |
| * the rightmost character in the pattern to the left. If the characters |
| * all match the pattern has been found. If a character does not match, |
| * the pattern is shifted right a distance that is the maximum of two |
| * functions, the bad character shift and the good suffix shift. This |
| * shift moves the attempted match position through the input more |
| * quickly than a naive one position at a time check. |
| * <p> |
| * The bad character shift is based on the character from the text that |
| * did not match. If the character does not appear in the pattern, the |
| * pattern can be shifted completely beyond the bad character. If the |
| * character does occur in the pattern, the pattern can be shifted to |
| * line the pattern up with the next occurrence of that character. |
| * <p> |
| * The good suffix shift is based on the idea that some subset on the right |
| * side of the pattern has matched. When a bad character is found, the |
| * pattern can be shifted right by the pattern length if the subset does |
| * not occur again in pattern, or by the amount of distance to the |
| * next occurrence of the subset in the pattern. |
| * |
| * Boyer-Moore search methods adapted from code by Amy Yu. |
| * |
| static class BnM extends Node { |
| int[] buffer; |
| int[] lastOcc; |
| int[] optoSft; |
| |
| /** |
| * Pre calculates arrays needed to generate the bad character |
| * shift and the good suffix shift. Only the last seven bits |
| * are used to see if chars match; This keeps the tables small |
| * and covers the heavily used ASCII range, but occasionally |
| * results in an aliased match for the bad character shift. |
| * |
| static Node optimize(Node node) { |
| if (!(node instanceof Slice)) { |
| return node; |
| } |
| |
| int[] src = ((Slice) node).buffer; |
| int patternLength = src.length; |
| // The BM algorithm requires a bit of overhead; |
| // If the pattern is short don't use it, since |
| // a shift larger than the pattern length cannot |
| // be used anyway. |
| if (patternLength < 4) { |
| return node; |
| } |
| int i, j; |
| int[] lastOcc = new int[128]; |
| int[] optoSft = new int[patternLength]; |
| // Precalculate part of the bad character shift |
| // It is a table for where in the pattern each |
| // lower 7-bit value occurs |
| for (i = 0; i < patternLength; i++) { |
| lastOcc[src[i]&0x7F] = i + 1; |
| } |
| // Precalculate the good suffix shift |
| // i is the shift amount being considered |
| NEXT: for (i = patternLength; i > 0; i--) { |
| // j is the beginning index of suffix being considered |
| for (j = patternLength - 1; j >= i; j--) { |
| // Testing for good suffix |
| if (src[j] == src[j-i]) { |
| // src[j..len] is a good suffix |
| optoSft[j-1] = i; |
| } else { |
| // No match. The array has already been |
| // filled up with correct values before. |
| continue NEXT; |
| } |
| } |
| // This fills up the remaining of optoSft |
| // any suffix can not have larger shift amount |
| // then its sub-suffix. Why??? |
| while (j > 0) { |
| optoSft[--j] = i; |
| } |
| } |
| // Set the guard value because of unicode compression |
| optoSft[patternLength-1] = 1; |
| if (node instanceof SliceS) |
| return new BnMS(src, lastOcc, optoSft, node.next); |
| return new BnM(src, lastOcc, optoSft, node.next); |
| } |
| BnM(int[] src, int[] lastOcc, int[] optoSft, Node next) { |
| this.buffer = src; |
| this.lastOcc = lastOcc; |
| this.optoSft = optoSft; |
| this.next = next; |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] src = buffer; |
| int patternLength = src.length; |
| int last = matcher.to - patternLength; |
| |
| // Loop over all possible match positions in text |
| NEXT: while (i <= last) { |
| // Loop over pattern from right to left |
| for (int j = patternLength - 1; j >= 0; j--) { |
| int ch = seq.charAt(i+j); |
| if (ch != src[j]) { |
| // Shift search to the right by the maximum of the |
| // bad character shift and the good suffix shift |
| i += Math.max(j + 1 - lastOcc[ch&0x7F], optoSft[j]); |
| continue NEXT; |
| } |
| } |
| // Entire pattern matched starting at i |
| matcher.first = i; |
| boolean ret = next.match(matcher, i + patternLength, seq); |
| if (ret) { |
| matcher.first = i; |
| matcher.groups[0] = matcher.first; |
| matcher.groups[1] = matcher.last; |
| return true; |
| } |
| i++; |
| } |
| // BnM is only used as the leading node in the unanchored case, |
| // and it replaced its Start() which always searches to the end |
| // if it doesn't find what it's looking for, so hitEnd is true. |
| matcher.hitEnd = true; |
| return false; |
| } |
| boolean study(TreeInfo info) { |
| info.minLength += buffer.length; |
| info.maxValid = false; |
| return next.study(info); |
| } |
| } |
| |
| /** |
| * Supplementary support version of BnM(). Unpaired surrogates are |
| * also handled by this class. |
| * |
| static final class BnMS extends BnM { |
| int lengthInChars; |
| |
| BnMS(int[] src, int[] lastOcc, int[] optoSft, Node next) { |
| super(src, lastOcc, optoSft, next); |
| for (int cp : buffer) { |
| lengthInChars += Character.charCount(cp); |
| } |
| } |
| boolean match(Matcher matcher, int i, CharSequence seq) { |
| int[] src = buffer; |
| int patternLength = src.length; |
| int last = matcher.to - lengthInChars; |
| |
| // Loop over all possible match positions in text |
| NEXT: while (i <= last) { |
| // Loop over pattern from right to left |
| int ch; |
| for (int j = countChars(seq, i, patternLength), x = patternLength - 1; |
| j > 0; j -= Character.charCount(ch), x--) { |
| ch = Character.codePointBefore(seq, i+j); |
| if (ch != src[x]) { |
| // Shift search to the right by the maximum of the |
| // bad character shift and the good suffix shift |
| int n = Math.max(x + 1 - lastOcc[ch&0x7F], optoSft[x]); |
| i += countChars(seq, i, n); |
| continue NEXT; |
| } |
| } |
| // Entire pattern matched starting at i |
| matcher.first = i; |
| boolean ret = next.match(matcher, i + lengthInChars, seq); |
| if (ret) { |
| matcher.first = i; |
| matcher.groups[0] = matcher.first; |
| matcher.groups[1] = matcher.last; |
| return true; |
| } |
| i += countChars(seq, i, 1); |
| } |
| matcher.hitEnd = true; |
| return false; |
| } |
| } |
| |
| @FunctionalInterface |
| static interface CharPredicate { |
| boolean is(int ch); |
| |
| default CharPredicate and(CharPredicate p) { |
| return ch -> is(ch) && p.is(ch); |
| } |
| default CharPredicate union(CharPredicate p) { |
| return ch -> is(ch) || p.is(ch); |
| } |
| default CharPredicate union(CharPredicate p1, |
| CharPredicate p2) { |
| return ch -> is(ch) || p1.is(ch) || p2.is(ch); |
| } |
| default CharPredicate negate() { |
| return ch -> !is(ch); |
| } |
| } |
| |
| static interface BmpCharPredicate extends CharPredicate { |
| |
| default CharPredicate and(CharPredicate p) { |
| if (p instanceof BmpCharPredicate) |
| return (BmpCharPredicate)(ch -> is(ch) && p.is(ch)); |
| return ch -> is(ch) && p.is(ch); |
| } |
| default CharPredicate union(CharPredicate p) { |
| if (p instanceof BmpCharPredicate) |
| return (BmpCharPredicate)(ch -> is(ch) || p.is(ch)); |
| return ch -> is(ch) || p.is(ch); |
| } |
| static CharPredicate union(CharPredicate... predicates) { |
| CharPredicate cp = ch -> { |
| for (CharPredicate p : predicates) { |
| if (!p.is(ch)) |
| return false; |
| } |
| return true; |
| }; |
| for (CharPredicate p : predicates) { |
| if (! (p instanceof BmpCharPredicate)) |
| return cp; |
| } |
| return (BmpCharPredicate)cp; |
| } |
| } |
| |
| /** |
| * matches a Perl vertical whitespace |
| * |
| static BmpCharPredicate VertWS() { |
| return cp -> (cp >= 0x0A && cp <= 0x0D) || |
| cp == 0x85 || cp == 0x2028 || cp == 0x2029; |
| } |
| |
| /** |
| * matches a Perl horizontal whitespace |
| * |
| static BmpCharPredicate HorizWS() { |
| return cp -> |
| cp == 0x09 || cp == 0x20 || cp == 0xa0 || cp == 0x1680 || |
| cp == 0x180e || cp >= 0x2000 && cp <= 0x200a || cp == 0x202f || |
| cp == 0x205f || cp == 0x3000; |
| } |
| |
| /** |
| * for the Unicode category ALL and the dot metacharacter when |
| * in dotall mode. |
| * |
| static CharPredicate ALL() { |
| return ch -> true; |
| } |
| |
| /** |
| * for the dot metacharacter when dotall is not enabled. |
| * |
| static CharPredicate DOT() { |
| return ch -> |
| (ch != '\n' && ch != '\r' |
| && (ch|1) != '\u2029' |
| && ch != '\u0085'); |
| } |
| |
| /** |
| * the dot metacharacter when dotall is not enabled but UNIX_LINES is enabled. |
| * |
| static CharPredicate UNIXDOT() { |
| return ch -> ch != '\n'; |
| } |
| |
| /** |
| * Indicate that matches a Supplementary Unicode character |
| * |
| static CharPredicate SingleS(int c) { |
| return ch -> ch == c; |
| } |
| |
| /** |
| * A bmp/optimized predicate of single |
| * |
| static BmpCharPredicate Single(int c) { |
| return ch -> ch == c; |
| } |
| |
| /** |
| * Case insensitive matches a given BMP character |
| * |
| static BmpCharPredicate SingleI(int lower, int upper) { |
| return ch -> ch == lower || ch == upper; |
| } |
| |
| /** |
| * Unicode case insensitive matches a given Unicode character |
| * |
| static CharPredicate SingleU(int lower) { |
| return ch -> lower == ch || |
| lower == Character.toLowerCase(Character.toUpperCase(ch)); |
| } |
| |
| private static boolean inRange(int lower, int ch, int upper) { |
| return lower <= ch && ch <= upper; |
| } |
| |
| /** |
| * Characters within a explicit value range |
| * |
| static CharPredicate Range(int lower, int upper) { |
| if (upper < Character.MIN_HIGH_SURROGATE || |
| lower > Character.MAX_LOW_SURROGATE && |
| upper < Character.MIN_SUPPLEMENTARY_CODE_POINT) |
| return (BmpCharPredicate)(ch -> inRange(lower, ch, upper)); |
| return ch -> inRange(lower, ch, upper); |
| } |
| |
| /** |
| * Characters within a explicit value range in a case insensitive manner. |
| * |
| static CharPredicate CIRange(int lower, int upper) { |
| return ch -> inRange(lower, ch, upper) || |
| ASCII.isAscii(ch) && |
| (inRange(lower, ASCII.toUpper(ch), upper) || |
| inRange(lower, ASCII.toLower(ch), upper)); |
| } |
| |
| static CharPredicate CIRangeU(int lower, int upper) { |
| return ch -> { |
| if (inRange(lower, ch, upper)) |
| return true; |
| int up = Character.toUpperCase(ch); |
| return inRange(lower, up, upper) || |
| inRange(lower, Character.toLowerCase(up), upper); |
| }; |
| } |
| |
| /** |
| * This must be the very first initializer. |
| * |
| static final Node accept = new Node(); |
| |
| static final Node lastAccept = new LastNode(); |
| */ |
| // END Android-removed: Reimplement matching logic via ICU4C. |
| |
| /** |
| * Creates a predicate that tests if this pattern is found in a given input |
| * string. |
| * |
| * @apiNote |
| * This method creates a predicate that behaves as if it creates a matcher |
| * from the input sequence and then calls {@code find}, for example a |
| * predicate of the form: |
| * <pre>{@code |
| * s -> matcher(s).find(); |
| * }</pre> |
| * |
| * @return The predicate which can be used for finding a match on a |
| * subsequence of a string |
| * @since 1.8 |
| * @see Matcher#find |
| */ |
| public Predicate<String> asPredicate() { |
| return s -> matcher(s).find(); |
| } |
| |
| /** |
| * Creates a predicate that tests if this pattern matches a given input string. |
| * |
| * @apiNote |
| * This method creates a predicate that behaves as if it creates a matcher |
| * from the input sequence and then calls {@code matches}, for example a |
| * predicate of the form: |
| * <pre>{@code |
| * s -> matcher(s).matches(); |
| * }</pre> |
| * |
| * @return The predicate which can be used for matching an input string |
| * against this pattern. |
| * @since 11 |
| * @see Matcher#matches |
| */ |
| public Predicate<String> asMatchPredicate() { |
| return s -> matcher(s).matches(); |
| } |
| |
| /** |
| * Creates a stream from the given input sequence around matches of this |
| * pattern. |
| * |
| * <p> The stream returned by this method contains each substring of the |
| * input sequence that is terminated by another subsequence that matches |
| * this pattern or is terminated by the end of the input sequence. The |
| * substrings in the stream are in the order in which they occur in the |
| * input. Trailing empty strings will be discarded and not encountered in |
| * the stream. |
| * |
| * <p> If this pattern does not match any subsequence of the input then |
| * the resulting stream has just one element, namely the input sequence in |
| * string form. |
| * |
| * <p> When there is a positive-width match at the beginning of the input |
| * sequence then an empty leading substring is included at the beginning |
| * of the stream. A zero-width match at the beginning however never produces |
| * such empty leading substring. |
| * |
| * <p> If the input sequence is mutable, it must remain constant during the |
| * execution of the terminal stream operation. Otherwise, the result of the |
| * terminal stream operation is undefined. |
| * |
| * @param input |
| * The character sequence to be split |
| * |
| * @return The stream of strings computed by splitting the input |
| * around matches of this pattern |
| * @see #split(CharSequence) |
| * @since 1.8 |
| */ |
| public Stream<String> splitAsStream(final CharSequence input) { |
| class MatcherIterator implements Iterator<String> { |
| private Matcher matcher; |
| // The start position of the next sub-sequence of input |
| // when current == input.length there are no more elements |
| private int current; |
| // null if the next element, if any, needs to obtained |
| private String nextElement; |
| // > 0 if there are N next empty elements |
| private int emptyElementCount; |
| |
| public String next() { |
| if (!hasNext()) |
| throw new NoSuchElementException(); |
| |
| if (emptyElementCount == 0) { |
| String n = nextElement; |
| nextElement = null; |
| return n; |
| } else { |
| emptyElementCount--; |
| return ""; |
| } |
| } |
| |
| public boolean hasNext() { |
| if (matcher == null) { |
| matcher = matcher(input); |
| // If the input is an empty string then the result can only be a |
| // stream of the input. Induce that by setting the empty |
| // element count to 1 |
| // Android-changed: Keep old behavior on Android 13 or below. http://b/286499139 |
| // emptyElementCount = input.length() == 0 ? 1 : 0; |
| if (input.length() == 0 |
| && VMRuntime.getSdkVersion() >= VersionCodes.UPSIDE_DOWN_CAKE |
| && Compatibility.isChangeEnabled( |
| SPLIT_AS_STREAM_RETURNS_SINGLE_EMPTY_STRING)) { |
| emptyElementCount = 1; |
| } else { |
| emptyElementCount = 0; |
| } |
| } |
| if (nextElement != null || emptyElementCount > 0) |
| return true; |
| |
| if (current == input.length()) |
| return false; |
| |
| // Consume the next matching element |
| // Count sequence of matching empty elements |
| while (matcher.find()) { |
| nextElement = input.subSequence(current, matcher.start()).toString(); |
| current = matcher.end(); |
| if (!nextElement.isEmpty()) { |
| return true; |
| } else if (current > 0) { // no empty leading substring for zero-width |
| // match at the beginning of the input |
| emptyElementCount++; |
| } |
| } |
| |
| // Consume last matching element |
| nextElement = input.subSequence(current, input.length()).toString(); |
| current = input.length(); |
| if (!nextElement.isEmpty()) { |
| return true; |
| } else { |
| // Ignore a terminal sequence of matching empty elements |
| emptyElementCount = 0; |
| nextElement = null; |
| return false; |
| } |
| } |
| } |
| return StreamSupport.stream(Spliterators.spliteratorUnknownSize( |
| new MatcherIterator(), Spliterator.ORDERED | Spliterator.NONNULL), false); |
| } |
| |
| // Android-added: Backward-compatible flag for splitAsStream() API. |
| /** |
| * Since Android 14, {@link Pattern#splitAsStream(CharSequence)} return a stream of a single |
| * empty String as described in the API documentation. Previously, given an empty string input, |
| * the method returns an empty stream. |
| * |
| * This flag is enabled for apps targeting Android 14+. |
| * |
| * @hide |
| */ |
| @ChangeId |
| @EnabledSince(targetSdkVersion = VersionCodes.UPSIDE_DOWN_CAKE) |
| public static final long SPLIT_AS_STREAM_RETURNS_SINGLE_EMPTY_STRING = 288845345L; |
| |
| } |
