| /* |
| * Copyright (c) 2005, 2015, 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. |
| */ |
| |
| /* |
| ******************************************************************************* |
| * Copyright (C) 1996-2015, International Business Machines Corporation and |
| * others. All Rights Reserved. |
| ******************************************************************************* |
| */ |
| package sun.text.normalizer; |
| |
| import java.io.IOException; |
| import java.text.ParsePosition; |
| import java.util.ArrayList; |
| import java.util.TreeSet; |
| |
| /** |
| * A mutable set of Unicode characters and multicharacter strings. |
| * Objects of this class represent <em>character classes</em> used |
| * in regular expressions. A character specifies a subset of Unicode |
| * code points. Legal code points are U+0000 to U+10FFFF, inclusive. |
| * |
| * Note: method freeze() will not only make the set immutable, but |
| * also makes important methods much higher performance: |
| * contains(c), containsNone(...), span(...), spanBack(...) etc. |
| * After the object is frozen, any subsequent call that wants to change |
| * the object will throw UnsupportedOperationException. |
| * |
| * <p>The UnicodeSet class is not designed to be subclassed. |
| * |
| * <p><code>UnicodeSet</code> supports two APIs. The first is the |
| * <em>operand</em> API that allows the caller to modify the value of |
| * a <code>UnicodeSet</code> object. It conforms to Java 2's |
| * <code>java.util.Set</code> interface, although |
| * <code>UnicodeSet</code> does not actually implement that |
| * interface. All methods of <code>Set</code> are supported, with the |
| * modification that they take a character range or single character |
| * instead of an <code>Object</code>, and they take a |
| * <code>UnicodeSet</code> instead of a <code>Collection</code>. The |
| * operand API may be thought of in terms of boolean logic: a boolean |
| * OR is implemented by <code>add</code>, a boolean AND is implemented |
| * by <code>retain</code>, a boolean XOR is implemented by |
| * <code>complement</code> taking an argument, and a boolean NOT is |
| * implemented by <code>complement</code> with no argument. In terms |
| * of traditional set theory function names, <code>add</code> is a |
| * union, <code>retain</code> is an intersection, <code>remove</code> |
| * is an asymmetric difference, and <code>complement</code> with no |
| * argument is a set complement with respect to the superset range |
| * <code>MIN_VALUE-MAX_VALUE</code> |
| * |
| * <p>The second API is the |
| * <code>applyPattern()</code>/<code>toPattern()</code> API from the |
| * <code>java.text.Format</code>-derived classes. Unlike the |
| * methods that add characters, add categories, and control the logic |
| * of the set, the method <code>applyPattern()</code> sets all |
| * attributes of a <code>UnicodeSet</code> at once, based on a |
| * string pattern. |
| * |
| * <p><b>Pattern syntax</b></p> |
| * |
| * Patterns are accepted by the constructors and the |
| * <code>applyPattern()</code> methods and returned by the |
| * <code>toPattern()</code> method. These patterns follow a syntax |
| * similar to that employed by version 8 regular expression character |
| * classes. Here are some simple examples: |
| * |
| * <blockquote> |
| * <table> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="left"><code>[]</code></td> |
| * <td valign="top">No characters</td> |
| * </tr><tr align="top"> |
| * <td nowrap valign="top" align="left"><code>[a]</code></td> |
| * <td valign="top">The character 'a'</td> |
| * </tr><tr align="top"> |
| * <td nowrap valign="top" align="left"><code>[ae]</code></td> |
| * <td valign="top">The characters 'a' and 'e'</td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top" align="left"><code>[a-e]</code></td> |
| * <td valign="top">The characters 'a' through 'e' inclusive, in Unicode code |
| * point order</td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top" align="left"><code>[\\u4E01]</code></td> |
| * <td valign="top">The character U+4E01</td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top" align="left"><code>[a{ab}{ac}]</code></td> |
| * <td valign="top">The character 'a' and the multicharacter strings "ab" and |
| * "ac"</td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top" align="left"><code>[\p{Lu}]</code></td> |
| * <td valign="top">All characters in the general category Uppercase Letter</td> |
| * </tr> |
| * </table> |
| * </blockquote> |
| * |
| * Any character may be preceded by a backslash in order to remove any special |
| * meaning. White space characters, as defined by the Unicode Pattern_White_Space property, are |
| * ignored, unless they are escaped. |
| * |
| * <p>Property patterns specify a set of characters having a certain |
| * property as defined by the Unicode standard. Both the POSIX-like |
| * "[:Lu:]" and the Perl-like syntax "\p{Lu}" are recognized. For a |
| * complete list of supported property patterns, see the User's Guide |
| * for UnicodeSet at |
| * <a href="http://www.icu-project.org/userguide/unicodeSet.html"> |
| * http://www.icu-project.org/userguide/unicodeSet.html</a>. |
| * Actual determination of property data is defined by the underlying |
| * Unicode database as implemented by UCharacter. |
| * |
| * <p>Patterns specify individual characters, ranges of characters, and |
| * Unicode property sets. When elements are concatenated, they |
| * specify their union. To complement a set, place a '^' immediately |
| * after the opening '['. Property patterns are inverted by modifying |
| * their delimiters; "[:^foo]" and "\P{foo}". In any other location, |
| * '^' has no special meaning. |
| * |
| * <p>Ranges are indicated by placing two a '-' between two |
| * characters, as in "a-z". This specifies the range of all |
| * characters from the left to the right, in Unicode order. If the |
| * left character is greater than or equal to the |
| * right character it is a syntax error. If a '-' occurs as the first |
| * character after the opening '[' or '[^', or if it occurs as the |
| * last character before the closing ']', then it is taken as a |
| * literal. Thus "[a\\-b]", "[-ab]", and "[ab-]" all indicate the same |
| * set of three characters, 'a', 'b', and '-'. |
| * |
| * <p>Sets may be intersected using the {@literal '&'} operator or the asymmetric |
| * set difference may be taken using the '-' operator, for example, |
| * "{@code [[:L:]&[\\u0000-\\u0FFF]]}" indicates the set of all Unicode letters |
| * with values less than 4096. Operators ({@literal '&'} and '|') have equal |
| * precedence and bind left-to-right. Thus |
| * "[[:L:]-[a-z]-[\\u0100-\\u01FF]]" is equivalent to |
| * "[[[:L:]-[a-z]]-[\\u0100-\\u01FF]]". This only really matters for |
| * difference; intersection is commutative. |
| * |
| * <table> |
| * <tr valign=top><td nowrap><code>[a]</code><td>The set containing 'a' |
| * <tr valign=top><td nowrap><code>[a-z]</code><td>The set containing 'a' |
| * through 'z' and all letters in between, in Unicode order |
| * <tr valign=top><td nowrap><code>[^a-z]</code><td>The set containing |
| * all characters but 'a' through 'z', |
| * that is, U+0000 through 'a'-1 and 'z'+1 through U+10FFFF |
| * <tr valign=top><td nowrap><code>[[<em>pat1</em>][<em>pat2</em>]]</code> |
| * <td>The union of sets specified by <em>pat1</em> and <em>pat2</em> |
| * <tr valign=top><td nowrap><code>[[<em>pat1</em>]&[<em>pat2</em>]]</code> |
| * <td>The intersection of sets specified by <em>pat1</em> and <em>pat2</em> |
| * <tr valign=top><td nowrap><code>[[<em>pat1</em>]-[<em>pat2</em>]]</code> |
| * <td>The asymmetric difference of sets specified by <em>pat1</em> and |
| * <em>pat2</em> |
| * <tr valign=top><td nowrap><code>[:Lu:] or \p{Lu}</code> |
| * <td>The set of characters having the specified |
| * Unicode property; in |
| * this case, Unicode uppercase letters |
| * <tr valign=top><td nowrap><code>[:^Lu:] or \P{Lu}</code> |
| * <td>The set of characters <em>not</em> having the given |
| * Unicode property |
| * </table> |
| * |
| * <p><b>Warning</b>: you cannot add an empty string ("") to a UnicodeSet.</p> |
| * |
| * <p><b>Formal syntax</b></p> |
| * |
| * <blockquote> |
| * <table> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>pattern := </code></td> |
| * <td valign="top"><code>('[' '^'? item* ']') | |
| * property</code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>item := </code></td> |
| * <td valign="top"><code>char | (char '-' char) | pattern-expr<br> |
| * </code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>pattern-expr := </code></td> |
| * <td valign="top"><code>pattern | pattern-expr pattern | |
| * pattern-expr op pattern<br> |
| * </code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>op := </code></td> |
| * <td valign="top"><code>'&' | '-'<br> |
| * </code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>special := </code></td> |
| * <td valign="top"><code>'[' | ']' | '-'<br> |
| * </code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>char := </code></td> |
| * <td valign="top"><em>any character that is not</em><code> special<br> |
| * | ('\\' </code><em>any character</em><code>)<br> |
| * | ('\u' hex hex hex hex)<br> |
| * </code></td> |
| * </tr> |
| * <tr align="top"> |
| * <td nowrap valign="top" align="right"><code>hex := </code></td> |
| * <td valign="top"><em>any character for which |
| * </em><code>Character.digit(c, 16)</code><em> |
| * returns a non-negative result</em></td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top" align="right"><code>property := </code></td> |
| * <td valign="top"><em>a Unicode property set pattern</em></td> |
| * </tr> |
| * </table> |
| * <br> |
| * <table border="1"> |
| * <tr> |
| * <td>Legend: <table> |
| * <tr> |
| * <td nowrap valign="top"><code>a := b</code></td> |
| * <td width="20" valign="top"> </td> |
| * <td valign="top"><code>a</code> may be replaced by <code>b</code> </td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top"><code>a?</code></td> |
| * <td valign="top"></td> |
| * <td valign="top">zero or one instance of <code>a</code><br> |
| * </td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top"><code>a*</code></td> |
| * <td valign="top"></td> |
| * <td valign="top">one or more instances of <code>a</code><br> |
| * </td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top"><code>a | b</code></td> |
| * <td valign="top"></td> |
| * <td valign="top">either <code>a</code> or <code>b</code><br> |
| * </td> |
| * </tr> |
| * <tr> |
| * <td nowrap valign="top"><code>'a'</code></td> |
| * <td valign="top"></td> |
| * <td valign="top">the literal string between the quotes </td> |
| * </tr> |
| * </table> |
| * </td> |
| * </tr> |
| * </table> |
| * </blockquote> |
| * <p>To iterate over contents of UnicodeSet, the following are available: |
| * <ul><li>{@link #ranges()} to iterate through the ranges</li> |
| * <li>{@link #strings()} to iterate through the strings</li> |
| * <li>{@link #iterator()} to iterate through the entire contents in a single loop. |
| * That method is, however, not particularly efficient, since it "boxes" each code point into a String. |
| * </ul> |
| * All of the above can be used in <b>for</b> loops. |
| * The {@link com.ibm.icu.text.UnicodeSetIterator UnicodeSetIterator} can also be used, but not in <b>for</b> loops. |
| * <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}. |
| * |
| * @author Alan Liu |
| * @stable ICU 2.0 |
| */ |
| class UnicodeSet { |
| |
| private static final int LOW = 0x000000; // LOW <= all valid values. ZERO for codepoints |
| private static final int HIGH = 0x110000; // HIGH > all valid values. 10000 for code units. |
| // 110000 for codepoints |
| |
| /** |
| * Minimum value that can be stored in a UnicodeSet. |
| * @stable ICU 2.0 |
| */ |
| public static final int MIN_VALUE = LOW; |
| |
| /** |
| * Maximum value that can be stored in a UnicodeSet. |
| * @stable ICU 2.0 |
| */ |
| public static final int MAX_VALUE = HIGH - 1; |
| |
| private int len; // length used; list may be longer to minimize reallocs |
| private int[] list; // MUST be terminated with HIGH |
| private int[] rangeList; // internal buffer |
| private int[] buffer; // internal buffer |
| |
| // NOTE: normally the field should be of type SortedSet; but that is missing a public clone!! |
| // is not private so that UnicodeSetIterator can get access |
| TreeSet<String> strings = new TreeSet<String>(); |
| |
| /** |
| * The pattern representation of this set. This may not be the |
| * most economical pattern. It is the pattern supplied to |
| * applyPattern(), with variables substituted and whitespace |
| * removed. For sets constructed without applyPattern(), or |
| * modified using the non-pattern API, this string will be null, |
| * indicating that toPattern() must generate a pattern |
| * representation from the inversion list. |
| */ |
| |
| private static final int START_EXTRA = 16; // initial storage. Must be >= 0 |
| private static final int GROW_EXTRA = START_EXTRA; // extra amount for growth. Must be >= 0 |
| |
| private static UnicodeSet INCLUSION = null; |
| |
| private volatile BMPSet bmpSet; // The set is frozen if bmpSet or stringSpan is not null. |
| private volatile UnicodeSetStringSpan stringSpan; |
| |
| //---------------------------------------------------------------- |
| // Public API |
| //---------------------------------------------------------------- |
| |
| /** |
| * Constructs an empty set. |
| * @stable ICU 2.0 |
| */ |
| private UnicodeSet() { |
| list = new int[1 + START_EXTRA]; |
| list[len++] = HIGH; |
| } |
| |
| /** |
| * Constructs a copy of an existing set. |
| * @stable ICU 2.0 |
| */ |
| private UnicodeSet(UnicodeSet other) { |
| set(other); |
| } |
| |
| /** |
| * Constructs a set containing the given range. If <code>end > |
| * start</code> then an empty set is created. |
| * |
| * @param start first character, inclusive, of range |
| * @param end last character, inclusive, of range |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet(int start, int end) { |
| this(); |
| complement(start, end); |
| } |
| |
| /** |
| * Constructs a set from the given pattern. See the class description |
| * for the syntax of the pattern language. Whitespace is ignored. |
| * @param pattern a string specifying what characters are in the set |
| * @exception java.lang.IllegalArgumentException if the pattern contains |
| * a syntax error. |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet(String pattern) { |
| this(); |
| applyPattern(pattern, null); |
| } |
| |
| /** |
| * Make this object represent the same set as <code>other</code>. |
| * @param other a <code>UnicodeSet</code> whose value will be |
| * copied to this object |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet set(UnicodeSet other) { |
| checkFrozen(); |
| list = other.list.clone(); |
| len = other.len; |
| strings = new TreeSet<String>(other.strings); |
| return this; |
| } |
| |
| /** |
| * Returns the number of elements in this set (its cardinality) |
| * Note than the elements of a set may include both individual |
| * codepoints and strings. |
| * |
| * @return the number of elements in this set (its cardinality). |
| * @stable ICU 2.0 |
| */ |
| public int size() { |
| int n = 0; |
| int count = getRangeCount(); |
| for (int i = 0; i < count; ++i) { |
| n += getRangeEnd(i) - getRangeStart(i) + 1; |
| } |
| return n + strings.size(); |
| } |
| |
| // for internal use, after checkFrozen has been called |
| private UnicodeSet add_unchecked(int start, int end) { |
| if (start < MIN_VALUE || start > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6)); |
| } |
| if (end < MIN_VALUE || end > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6)); |
| } |
| if (start < end) { |
| add(range(start, end), 2, 0); |
| } else if (start == end) { |
| add(start); |
| } |
| return this; |
| } |
| |
| /** |
| * Adds the specified character to this set if it is not already |
| * present. If this set already contains the specified character, |
| * the call leaves this set unchanged. |
| * @stable ICU 2.0 |
| */ |
| public final UnicodeSet add(int c) { |
| checkFrozen(); |
| return add_unchecked(c); |
| } |
| |
| // for internal use only, after checkFrozen has been called |
| private final UnicodeSet add_unchecked(int c) { |
| if (c < MIN_VALUE || c > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6)); |
| } |
| |
| // find smallest i such that c < list[i] |
| // if odd, then it is IN the set |
| // if even, then it is OUT of the set |
| int i = findCodePoint(c); |
| |
| // already in set? |
| if ((i & 1) != 0) return this; |
| |
| // HIGH is 0x110000 |
| // assert(list[len-1] == HIGH); |
| |
| // empty = [HIGH] |
| // [start_0, limit_0, start_1, limit_1, HIGH] |
| |
| // [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH] |
| // ^ |
| // list[i] |
| |
| // i == 0 means c is before the first range |
| |
| if (c == list[i]-1) { |
| // c is before start of next range |
| list[i] = c; |
| // if we touched the HIGH mark, then add a new one |
| if (c == MAX_VALUE) { |
| ensureCapacity(len+1); |
| list[len++] = HIGH; |
| } |
| if (i > 0 && c == list[i-1]) { |
| // collapse adjacent ranges |
| |
| // [..., start_k-1, c, c, limit_k, ..., HIGH] |
| // ^ |
| // list[i] |
| System.arraycopy(list, i+1, list, i-1, len-i-1); |
| len -= 2; |
| } |
| } |
| |
| else if (i > 0 && c == list[i-1]) { |
| // c is after end of prior range |
| list[i-1]++; |
| // no need to chcek for collapse here |
| } |
| |
| else { |
| // At this point we know the new char is not adjacent to |
| // any existing ranges, and it is not 10FFFF. |
| |
| |
| // [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH] |
| // ^ |
| // list[i] |
| |
| // [..., start_k-1, limit_k-1, c, c+1, start_k, limit_k, ..., HIGH] |
| // ^ |
| // list[i] |
| |
| // Don't use ensureCapacity() to save on copying. |
| // NOTE: This has no measurable impact on performance, |
| // but it might help in some usage patterns. |
| if (len+2 > list.length) { |
| int[] temp = new int[len + 2 + GROW_EXTRA]; |
| if (i != 0) System.arraycopy(list, 0, temp, 0, i); |
| System.arraycopy(list, i, temp, i+2, len-i); |
| list = temp; |
| } else { |
| System.arraycopy(list, i, list, i+2, len-i); |
| } |
| |
| list[i] = c; |
| list[i+1] = c+1; |
| len += 2; |
| } |
| |
| return this; |
| } |
| |
| /** |
| * Adds the specified multicharacter to this set if it is not already |
| * present. If this set already contains the multicharacter, |
| * the call leaves this set unchanged. |
| * Thus {@code "ch" => {"ch"}} |
| * <br><b>Warning: you cannot add an empty string ("") to a UnicodeSet.</b> |
| * @param s the source string |
| * @return this object, for chaining |
| * @stable ICU 2.0 |
| */ |
| public final UnicodeSet add(CharSequence s) { |
| checkFrozen(); |
| int cp = getSingleCP(s); |
| if (cp < 0) { |
| strings.add(s.toString()); |
| } else { |
| add_unchecked(cp, cp); |
| } |
| return this; |
| } |
| |
| /** |
| * Utility for getting code point from single code point CharSequence. |
| * See the public UTF16.getSingleCodePoint() |
| * @return a code point IF the string consists of a single one. |
| * otherwise returns -1. |
| * @param s to test |
| */ |
| private static int getSingleCP(CharSequence s) { |
| if (s.length() < 1) { |
| throw new IllegalArgumentException("Can't use zero-length strings in UnicodeSet"); |
| } |
| if (s.length() > 2) return -1; |
| if (s.length() == 1) return s.charAt(0); |
| |
| // at this point, len = 2 |
| int cp = UTF16.charAt(s, 0); |
| if (cp > 0xFFFF) { // is surrogate pair |
| return cp; |
| } |
| return -1; |
| } |
| |
| /** |
| * Complements the specified range in this set. Any character in |
| * the range will be removed if it is in this set, or will be |
| * added if it is not in this set. If {@code end > start} |
| * then an empty range is complemented, leaving the set unchanged. |
| * |
| * @param start first character, inclusive, of range to be removed |
| * from this set. |
| * @param end last character, inclusive, of range to be removed |
| * from this set. |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet complement(int start, int end) { |
| checkFrozen(); |
| if (start < MIN_VALUE || start > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6)); |
| } |
| if (end < MIN_VALUE || end > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6)); |
| } |
| if (start <= end) { |
| xor(range(start, end), 2, 0); |
| } |
| return this; |
| } |
| |
| /** |
| * Returns true if this set contains the given character. |
| * @param c character to be checked for containment |
| * @return true if the test condition is met |
| * @stable ICU 2.0 |
| */ |
| public boolean contains(int c) { |
| if (c < MIN_VALUE || c > MAX_VALUE) { |
| throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6)); |
| } |
| if (bmpSet != null) { |
| return bmpSet.contains(c); |
| } |
| if (stringSpan != null) { |
| return stringSpan.contains(c); |
| } |
| |
| /* |
| // Set i to the index of the start item greater than ch |
| // We know we will terminate without length test! |
| int i = -1; |
| while (true) { |
| if (c < list[++i]) break; |
| } |
| */ |
| |
| int i = findCodePoint(c); |
| |
| return ((i & 1) != 0); // return true if odd |
| } |
| |
| /** |
| * Returns the smallest value i such that c < list[i]. Caller |
| * must ensure that c is a legal value or this method will enter |
| * an infinite loop. This method performs a binary search. |
| * @param c a character in the range MIN_VALUE..MAX_VALUE |
| * inclusive |
| * @return the smallest integer i in the range 0..len-1, |
| * inclusive, such that c < list[i] |
| */ |
| private final int findCodePoint(int c) { |
| /* Examples: |
| findCodePoint(c) |
| set list[] c=0 1 3 4 7 8 |
| === ============== =========== |
| [] [110000] 0 0 0 0 0 0 |
| [\u0000-\u0003] [0, 4, 110000] 1 1 1 2 2 2 |
| [\u0004-\u0007] [4, 8, 110000] 0 0 0 1 1 2 |
| [:all:] [0, 110000] 1 1 1 1 1 1 |
| */ |
| |
| // Return the smallest i such that c < list[i]. Assume |
| // list[len - 1] == HIGH and that c is legal (0..HIGH-1). |
| if (c < list[0]) return 0; |
| // High runner test. c is often after the last range, so an |
| // initial check for this condition pays off. |
| if (len >= 2 && c >= list[len-2]) return len-1; |
| int lo = 0; |
| int hi = len - 1; |
| // invariant: c >= list[lo] |
| // invariant: c < list[hi] |
| for (;;) { |
| int i = (lo + hi) >>> 1; |
| if (i == lo) return hi; |
| if (c < list[i]) { |
| hi = i; |
| } else { |
| lo = i; |
| } |
| } |
| } |
| |
| /** |
| * Retains only the elements in this set that are contained in the |
| * specified set. In other words, removes from this set all of |
| * its elements that are not contained in the specified set. This |
| * operation effectively modifies this set so that its value is |
| * the <i>intersection</i> of the two sets. |
| * |
| * @param c set that defines which elements this set will retain. |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet retainAll(UnicodeSet c) { |
| checkFrozen(); |
| retain(c.list, c.len, 0); |
| strings.retainAll(c.strings); |
| return this; |
| } |
| |
| /** |
| * Removes all of the elements from this set. This set will be |
| * empty after this call returns. |
| * @stable ICU 2.0 |
| */ |
| public UnicodeSet clear() { |
| checkFrozen(); |
| list[0] = HIGH; |
| len = 1; |
| strings.clear(); |
| return this; |
| } |
| |
| /** |
| * Iteration method that returns the number of ranges contained in |
| * this set. |
| * @see #getRangeStart |
| * @see #getRangeEnd |
| * @stable ICU 2.0 |
| */ |
| public int getRangeCount() { |
| return len/2; |
| } |
| |
| /** |
| * Iteration method that returns the first character in the |
| * specified range of this set. |
| * @exception ArrayIndexOutOfBoundsException if index is outside |
| * the range <code>0..getRangeCount()-1</code> |
| * @see #getRangeCount |
| * @see #getRangeEnd |
| * @stable ICU 2.0 |
| */ |
| public int getRangeStart(int index) { |
| return list[index*2]; |
| } |
| |
| /** |
| * Iteration method that returns the last character in the |
| * specified range of this set. |
| * @exception ArrayIndexOutOfBoundsException if index is outside |
| * the range <code>0..getRangeCount()-1</code> |
| * @see #getRangeStart |
| * @see #getRangeEnd |
| * @stable ICU 2.0 |
| */ |
| public int getRangeEnd(int index) { |
| return (list[index*2 + 1] - 1); |
| } |
| |
| //---------------------------------------------------------------- |
| // Implementation: Pattern parsing |
| //---------------------------------------------------------------- |
| |
| /** |
| * Parses the given pattern, starting at the given position. The character |
| * at pattern.charAt(pos.getIndex()) must be '[', or the parse fails. |
| * Parsing continues until the corresponding closing ']'. If a syntax error |
| * is encountered between the opening and closing brace, the parse fails. |
| * Upon return from a successful parse, the ParsePosition is updated to |
| * point to the character following the closing ']', and an inversion |
| * list for the parsed pattern is returned. This method |
| * calls itself recursively to parse embedded subpatterns. |
| * |
| * @param pattern the string containing the pattern to be parsed. The |
| * portion of the string from pos.getIndex(), which must be a '[', to the |
| * corresponding closing ']', is parsed. |
| * @param pos upon entry, the position at which to being parsing. The |
| * character at pattern.charAt(pos.getIndex()) must be a '['. Upon return |
| * from a successful parse, pos.getIndex() is either the character after the |
| * closing ']' of the parsed pattern, or pattern.length() if the closing ']' |
| * is the last character of the pattern string. |
| * @return an inversion list for the parsed substring |
| * of <code>pattern</code> |
| * @exception java.lang.IllegalArgumentException if the parse fails. |
| */ |
| private UnicodeSet applyPattern(String pattern, |
| ParsePosition pos) { |
| if ("[:age=3.2:]".equals(pattern)) { |
| checkFrozen(); |
| VersionInfo version = VersionInfo.getInstance("3.2"); |
| applyFilter(new VersionFilter(version), UCharacterProperty.SRC_PROPSVEC); |
| } else { |
| throw new IllegalStateException("UnicodeSet.applyPattern(unexpected pattern " |
| + pattern + ")"); |
| } |
| |
| return this; |
| } |
| |
| //---------------------------------------------------------------- |
| // Implementation: Utility methods |
| //---------------------------------------------------------------- |
| |
| private void ensureCapacity(int newLen) { |
| if (newLen <= list.length) return; |
| int[] temp = new int[newLen + GROW_EXTRA]; |
| System.arraycopy(list, 0, temp, 0, len); |
| list = temp; |
| } |
| |
| private void ensureBufferCapacity(int newLen) { |
| if (buffer != null && newLen <= buffer.length) return; |
| buffer = new int[newLen + GROW_EXTRA]; |
| } |
| |
| /** |
| * Assumes start <= end. |
| */ |
| private int[] range(int start, int end) { |
| if (rangeList == null) { |
| rangeList = new int[] { start, end+1, HIGH }; |
| } else { |
| rangeList[0] = start; |
| rangeList[1] = end+1; |
| } |
| return rangeList; |
| } |
| |
| //---------------------------------------------------------------- |
| // Implementation: Fundamental operations |
| //---------------------------------------------------------------- |
| |
| // polarity = 0, 3 is normal: x xor y |
| // polarity = 1, 2: x xor ~y == x === y |
| |
| private UnicodeSet xor(int[] other, int otherLen, int polarity) { |
| ensureBufferCapacity(len + otherLen); |
| int i = 0, j = 0, k = 0; |
| int a = list[i++]; |
| int b; |
| if (polarity == 1 || polarity == 2) { |
| b = LOW; |
| if (other[j] == LOW) { // skip base if already LOW |
| ++j; |
| b = other[j]; |
| } |
| } else { |
| b = other[j++]; |
| } |
| // simplest of all the routines |
| // sort the values, discarding identicals! |
| while (true) { |
| if (a < b) { |
| buffer[k++] = a; |
| a = list[i++]; |
| } else if (b < a) { |
| buffer[k++] = b; |
| b = other[j++]; |
| } else if (a != HIGH) { // at this point, a == b |
| // discard both values! |
| a = list[i++]; |
| b = other[j++]; |
| } else { // DONE! |
| buffer[k++] = HIGH; |
| len = k; |
| break; |
| } |
| } |
| // swap list and buffer |
| int[] temp = list; |
| list = buffer; |
| buffer = temp; |
| return this; |
| } |
| |
| // polarity = 0 is normal: x union y |
| // polarity = 2: x union ~y |
| // polarity = 1: ~x union y |
| // polarity = 3: ~x union ~y |
| |
| private UnicodeSet add(int[] other, int otherLen, int polarity) { |
| ensureBufferCapacity(len + otherLen); |
| int i = 0, j = 0, k = 0; |
| int a = list[i++]; |
| int b = other[j++]; |
| // change from xor is that we have to check overlapping pairs |
| // polarity bit 1 means a is second, bit 2 means b is. |
| main: |
| while (true) { |
| switch (polarity) { |
| case 0: // both first; take lower if unequal |
| if (a < b) { // take a |
| // Back up over overlapping ranges in buffer[] |
| if (k > 0 && a <= buffer[k-1]) { |
| // Pick latter end value in buffer[] vs. list[] |
| a = max(list[i], buffer[--k]); |
| } else { |
| // No overlap |
| buffer[k++] = a; |
| a = list[i]; |
| } |
| i++; // Common if/else code factored out |
| polarity ^= 1; |
| } else if (b < a) { // take b |
| if (k > 0 && b <= buffer[k-1]) { |
| b = max(other[j], buffer[--k]); |
| } else { |
| buffer[k++] = b; |
| b = other[j]; |
| } |
| j++; |
| polarity ^= 2; |
| } else { // a == b, take a, drop b |
| if (a == HIGH) break main; |
| // This is symmetrical; it doesn't matter if |
| // we backtrack with a or b. - liu |
| if (k > 0 && a <= buffer[k-1]) { |
| a = max(list[i], buffer[--k]); |
| } else { |
| // No overlap |
| buffer[k++] = a; |
| a = list[i]; |
| } |
| i++; |
| polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| case 3: // both second; take higher if unequal, and drop other |
| if (b <= a) { // take a |
| if (a == HIGH) break main; |
| buffer[k++] = a; |
| } else { // take b |
| if (b == HIGH) break main; |
| buffer[k++] = b; |
| } |
| a = list[i++]; polarity ^= 1; // factored common code |
| b = other[j++]; polarity ^= 2; |
| break; |
| case 1: // a second, b first; if b < a, overlap |
| if (a < b) { // no overlap, take a |
| buffer[k++] = a; a = list[i++]; polarity ^= 1; |
| } else if (b < a) { // OVERLAP, drop b |
| b = other[j++]; polarity ^= 2; |
| } else { // a == b, drop both! |
| if (a == HIGH) break main; |
| a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| case 2: // a first, b second; if a < b, overlap |
| if (b < a) { // no overlap, take b |
| buffer[k++] = b; b = other[j++]; polarity ^= 2; |
| } else if (a < b) { // OVERLAP, drop a |
| a = list[i++]; polarity ^= 1; |
| } else { // a == b, drop both! |
| if (a == HIGH) break main; |
| a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| } |
| } |
| buffer[k++] = HIGH; // terminate |
| len = k; |
| // swap list and buffer |
| int[] temp = list; |
| list = buffer; |
| buffer = temp; |
| return this; |
| } |
| |
| // polarity = 0 is normal: x intersect y |
| // polarity = 2: x intersect ~y == set-minus |
| // polarity = 1: ~x intersect y |
| // polarity = 3: ~x intersect ~y |
| |
| private UnicodeSet retain(int[] other, int otherLen, int polarity) { |
| ensureBufferCapacity(len + otherLen); |
| int i = 0, j = 0, k = 0; |
| int a = list[i++]; |
| int b = other[j++]; |
| // change from xor is that we have to check overlapping pairs |
| // polarity bit 1 means a is second, bit 2 means b is. |
| main: |
| while (true) { |
| switch (polarity) { |
| case 0: // both first; drop the smaller |
| if (a < b) { // drop a |
| a = list[i++]; polarity ^= 1; |
| } else if (b < a) { // drop b |
| b = other[j++]; polarity ^= 2; |
| } else { // a == b, take one, drop other |
| if (a == HIGH) break main; |
| buffer[k++] = a; a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| case 3: // both second; take lower if unequal |
| if (a < b) { // take a |
| buffer[k++] = a; a = list[i++]; polarity ^= 1; |
| } else if (b < a) { // take b |
| buffer[k++] = b; b = other[j++]; polarity ^= 2; |
| } else { // a == b, take one, drop other |
| if (a == HIGH) break main; |
| buffer[k++] = a; a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| case 1: // a second, b first; |
| if (a < b) { // NO OVERLAP, drop a |
| a = list[i++]; polarity ^= 1; |
| } else if (b < a) { // OVERLAP, take b |
| buffer[k++] = b; b = other[j++]; polarity ^= 2; |
| } else { // a == b, drop both! |
| if (a == HIGH) break main; |
| a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| case 2: // a first, b second; if a < b, overlap |
| if (b < a) { // no overlap, drop b |
| b = other[j++]; polarity ^= 2; |
| } else if (a < b) { // OVERLAP, take a |
| buffer[k++] = a; a = list[i++]; polarity ^= 1; |
| } else { // a == b, drop both! |
| if (a == HIGH) break main; |
| a = list[i++]; polarity ^= 1; |
| b = other[j++]; polarity ^= 2; |
| } |
| break; |
| } |
| } |
| buffer[k++] = HIGH; // terminate |
| len = k; |
| // swap list and buffer |
| int[] temp = list; |
| list = buffer; |
| buffer = temp; |
| return this; |
| } |
| |
| private static final int max(int a, int b) { |
| return (a > b) ? a : b; |
| } |
| |
| //---------------------------------------------------------------- |
| // Generic filter-based scanning code |
| //---------------------------------------------------------------- |
| |
| private static interface Filter { |
| boolean contains(int codePoint); |
| } |
| |
| private static final VersionInfo NO_VERSION = VersionInfo.getInstance(0, 0, 0, 0); |
| |
| private static class VersionFilter implements Filter { |
| VersionInfo version; |
| VersionFilter(VersionInfo version) { this.version = version; } |
| public boolean contains(int ch) { |
| VersionInfo v = UCharacter.getAge(ch); |
| // Reference comparison ok; VersionInfo caches and reuses |
| // unique objects. |
| return v != NO_VERSION && |
| v.compareTo(version) <= 0; |
| } |
| } |
| |
| private static synchronized UnicodeSet getInclusions(int src) { |
| if (src != UCharacterProperty.SRC_PROPSVEC) { |
| throw new IllegalStateException("UnicodeSet.getInclusions(unknown src "+src+")"); |
| } |
| |
| if (INCLUSION == null) { |
| UnicodeSet incl = new UnicodeSet(); |
| UCharacterProperty.INSTANCE.upropsvec_addPropertyStarts(incl); |
| INCLUSION = incl; |
| } |
| return INCLUSION; |
| } |
| |
| /** |
| * Generic filter-based scanning code for UCD property UnicodeSets. |
| */ |
| private UnicodeSet applyFilter(Filter filter, int src) { |
| // Logically, walk through all Unicode characters, noting the start |
| // and end of each range for which filter.contain(c) is |
| // true. Add each range to a set. |
| // |
| // To improve performance, use an inclusions set which |
| // encodes information about character ranges that are known |
| // to have identical properties. |
| // getInclusions(src) contains exactly the first characters of |
| // same-value ranges for the given properties "source". |
| |
| clear(); |
| |
| int startHasProperty = -1; |
| UnicodeSet inclusions = getInclusions(src); |
| int limitRange = inclusions.getRangeCount(); |
| |
| for (int j=0; j<limitRange; ++j) { |
| // get current range |
| int start = inclusions.getRangeStart(j); |
| int end = inclusions.getRangeEnd(j); |
| |
| // for all the code points in the range, process |
| for (int ch = start; ch <= end; ++ch) { |
| // only add to the unicodeset on inflection points -- |
| // where the hasProperty value changes to false |
| if (filter.contains(ch)) { |
| if (startHasProperty < 0) { |
| startHasProperty = ch; |
| } |
| } else if (startHasProperty >= 0) { |
| add_unchecked(startHasProperty, ch-1); |
| startHasProperty = -1; |
| } |
| } |
| } |
| if (startHasProperty >= 0) { |
| add_unchecked(startHasProperty, 0x10FFFF); |
| } |
| |
| return this; |
| } |
| |
| /** |
| * Is this frozen, according to the Freezable interface? |
| * |
| * @return value |
| * @stable ICU 3.8 |
| */ |
| public boolean isFrozen() { |
| return (bmpSet != null || stringSpan != null); |
| } |
| |
| /** |
| * Freeze this class, according to the Freezable interface. |
| * |
| * @return this |
| * @stable ICU 4.4 |
| */ |
| public UnicodeSet freeze() { |
| if (!isFrozen()) { |
| // Do most of what compact() does before freezing because |
| // compact() will not work when the set is frozen. |
| // Small modification: Don't shrink if the savings would be tiny (<=GROW_EXTRA). |
| |
| // Delete buffer first to defragment memory less. |
| buffer = null; |
| if (list.length > (len + GROW_EXTRA)) { |
| // Make the capacity equal to len or 1. |
| // We don't want to realloc of 0 size. |
| int capacity = (len == 0) ? 1 : len; |
| int[] oldList = list; |
| list = new int[capacity]; |
| for (int i = capacity; i-- > 0;) { |
| list[i] = oldList[i]; |
| } |
| } |
| |
| // Optimize contains() and span() and similar functions. |
| if (!strings.isEmpty()) { |
| stringSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), UnicodeSetStringSpan.ALL); |
| } |
| if (stringSpan == null || !stringSpan.needsStringSpanUTF16()) { |
| // Optimize for code point spans. |
| // There are no strings, or |
| // all strings are irrelevant for span() etc. because |
| // all of each string's code points are contained in this set. |
| // However, fully contained strings are relevant for spanAndCount(), |
| // so we create both objects. |
| bmpSet = new BMPSet(list, len); |
| } |
| } |
| return this; |
| } |
| |
| /** |
| * Span a string using this UnicodeSet. |
| * <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}. |
| * @param s The string to be spanned |
| * @param spanCondition The span condition |
| * @return the length of the span |
| * @stable ICU 4.4 |
| */ |
| public int span(CharSequence s, SpanCondition spanCondition) { |
| return span(s, 0, spanCondition); |
| } |
| |
| /** |
| * Span a string using this UnicodeSet. |
| * If the start index is less than 0, span will start from 0. |
| * If the start index is greater than the string length, span returns the string length. |
| * <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}. |
| * @param s The string to be spanned |
| * @param start The start index that the span begins |
| * @param spanCondition The span condition |
| * @return the string index which ends the span (i.e. exclusive) |
| * @stable ICU 4.4 |
| */ |
| public int span(CharSequence s, int start, SpanCondition spanCondition) { |
| int end = s.length(); |
| if (start < 0) { |
| start = 0; |
| } else if (start >= end) { |
| return end; |
| } |
| if (bmpSet != null) { |
| // Frozen set without strings, or no string is relevant for span(). |
| return bmpSet.span(s, start, spanCondition, null); |
| } |
| if (stringSpan != null) { |
| return stringSpan.span(s, start, spanCondition); |
| } else if (!strings.isEmpty()) { |
| int which = spanCondition == SpanCondition.NOT_CONTAINED ? UnicodeSetStringSpan.FWD_UTF16_NOT_CONTAINED |
| : UnicodeSetStringSpan.FWD_UTF16_CONTAINED; |
| UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which); |
| if (strSpan.needsStringSpanUTF16()) { |
| return strSpan.span(s, start, spanCondition); |
| } |
| } |
| |
| return spanCodePointsAndCount(s, start, spanCondition, null); |
| } |
| |
| /** |
| * Same as span() but also counts the smallest number of set elements on any path across the span. |
| * <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}. |
| * @param outCount An output-only object (must not be null) for returning the count. |
| * @return the limit (exclusive end) of the span |
| */ |
| public int spanAndCount(CharSequence s, int start, SpanCondition spanCondition, OutputInt outCount) { |
| if (outCount == null) { |
| throw new IllegalArgumentException("outCount must not be null"); |
| } |
| int end = s.length(); |
| if (start < 0) { |
| start = 0; |
| } else if (start >= end) { |
| return end; |
| } |
| if (stringSpan != null) { |
| // We might also have bmpSet != null, |
| // but fully-contained strings are relevant for counting elements. |
| return stringSpan.spanAndCount(s, start, spanCondition, outCount); |
| } else if (bmpSet != null) { |
| return bmpSet.span(s, start, spanCondition, outCount); |
| } else if (!strings.isEmpty()) { |
| int which = spanCondition == SpanCondition.NOT_CONTAINED ? UnicodeSetStringSpan.FWD_UTF16_NOT_CONTAINED |
| : UnicodeSetStringSpan.FWD_UTF16_CONTAINED; |
| which |= UnicodeSetStringSpan.WITH_COUNT; |
| UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which); |
| return strSpan.spanAndCount(s, start, spanCondition, outCount); |
| } |
| |
| return spanCodePointsAndCount(s, start, spanCondition, outCount); |
| } |
| |
| private int spanCodePointsAndCount(CharSequence s, int start, |
| SpanCondition spanCondition, OutputInt outCount) { |
| // Pin to 0/1 values. |
| boolean spanContained = (spanCondition != SpanCondition.NOT_CONTAINED); |
| |
| int c; |
| int next = start; |
| int length = s.length(); |
| int count = 0; |
| do { |
| c = Character.codePointAt(s, next); |
| if (spanContained != contains(c)) { |
| break; |
| } |
| ++count; |
| next += Character.charCount(c); |
| } while (next < length); |
| if (outCount != null) { outCount.value = count; } |
| return next; |
| } |
| |
| /** |
| * Span a string backwards (from the fromIndex) using this UnicodeSet. |
| * If the fromIndex is less than 0, spanBack will return 0. |
| * If fromIndex is greater than the string length, spanBack will start from the string length. |
| * <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}. |
| * @param s The string to be spanned |
| * @param fromIndex The index of the char (exclusive) that the string should be spanned backwards |
| * @param spanCondition The span condition |
| * @return The string index which starts the span (i.e. inclusive). |
| * @stable ICU 4.4 |
| */ |
| public int spanBack(CharSequence s, int fromIndex, SpanCondition spanCondition) { |
| if (fromIndex <= 0) { |
| return 0; |
| } |
| if (fromIndex > s.length()) { |
| fromIndex = s.length(); |
| } |
| if (bmpSet != null) { |
| // Frozen set without strings, or no string is relevant for spanBack(). |
| return bmpSet.spanBack(s, fromIndex, spanCondition); |
| } |
| if (stringSpan != null) { |
| return stringSpan.spanBack(s, fromIndex, spanCondition); |
| } else if (!strings.isEmpty()) { |
| int which = (spanCondition == SpanCondition.NOT_CONTAINED) |
| ? UnicodeSetStringSpan.BACK_UTF16_NOT_CONTAINED |
| : UnicodeSetStringSpan.BACK_UTF16_CONTAINED; |
| UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which); |
| if (strSpan.needsStringSpanUTF16()) { |
| return strSpan.spanBack(s, fromIndex, spanCondition); |
| } |
| } |
| |
| // Pin to 0/1 values. |
| boolean spanContained = (spanCondition != SpanCondition.NOT_CONTAINED); |
| |
| int c; |
| int prev = fromIndex; |
| do { |
| c = Character.codePointBefore(s, prev); |
| if (spanContained != contains(c)) { |
| break; |
| } |
| prev -= Character.charCount(c); |
| } while (prev > 0); |
| return prev; |
| } |
| |
| /** |
| * Clone a thawed version of this class, according to the Freezable interface. |
| * @return the clone, not frozen |
| * @stable ICU 4.4 |
| */ |
| public UnicodeSet cloneAsThawed() { |
| UnicodeSet result = new UnicodeSet(this); |
| assert !result.isFrozen(); |
| return result; |
| } |
| |
| // internal function |
| private void checkFrozen() { |
| if (isFrozen()) { |
| throw new UnsupportedOperationException("Attempt to modify frozen object"); |
| } |
| } |
| |
| /** |
| * Argument values for whether span() and similar functions continue while the current character is contained vs. |
| * not contained in the set. |
| * <p> |
| * The functionality is straightforward for sets with only single code points, without strings (which is the common |
| * case): |
| * <ul> |
| * <li>CONTAINED and SIMPLE work the same. |
| * <li>CONTAINED and SIMPLE are inverses of NOT_CONTAINED. |
| * <li>span() and spanBack() partition any string the |
| * same way when alternating between span(NOT_CONTAINED) and span(either "contained" condition). |
| * <li>Using a |
| * complemented (inverted) set and the opposite span conditions yields the same results. |
| * </ul> |
| * When a set contains multi-code point strings, then these statements may not be true, depending on the strings in |
| * the set (for example, whether they overlap with each other) and the string that is processed. For a set with |
| * strings: |
| * <ul> |
| * <li>The complement of the set contains the opposite set of code points, but the same set of strings. |
| * Therefore, complementing both the set and the span conditions may yield different results. |
| * <li>When starting spans |
| * at different positions in a string (span(s, ...) vs. span(s+1, ...)) the ends of the spans may be different |
| * because a set string may start before the later position. |
| * <li>span(SIMPLE) may be shorter than |
| * span(CONTAINED) because it will not recursively try all possible paths. For example, with a set which |
| * contains the three strings "xy", "xya" and "ax", span("xyax", CONTAINED) will return 4 but span("xyax", |
| * SIMPLE) will return 3. span(SIMPLE) will never be longer than span(CONTAINED). |
| * <li>With either "contained" condition, span() and spanBack() may partition a string in different ways. For example, |
| * with a set which contains the two strings "ab" and "ba", and when processing the string "aba", span() will yield |
| * contained/not-contained boundaries of { 0, 2, 3 } while spanBack() will yield boundaries of { 0, 1, 3 }. |
| * </ul> |
| * Note: If it is important to get the same boundaries whether iterating forward or backward through a string, then |
| * either only span() should be used and the boundaries cached for backward operation, or an ICU BreakIterator could |
| * be used. |
| * <p> |
| * Note: Unpaired surrogates are treated like surrogate code points. Similarly, set strings match only on code point |
| * boundaries, never in the middle of a surrogate pair. |
| * |
| * @stable ICU 4.4 |
| */ |
| public enum SpanCondition { |
| /** |
| * Continues a span() while there is no set element at the current position. |
| * Increments by one code point at a time. |
| * Stops before the first set element (character or string). |
| * (For code points only, this is like while contains(current)==false). |
| * <p> |
| * When span() returns, the substring between where it started and the position it returned consists only of |
| * characters that are not in the set, and none of its strings overlap with the span. |
| * |
| * @stable ICU 4.4 |
| */ |
| NOT_CONTAINED, |
| |
| /** |
| * Spans the longest substring that is a concatenation of set elements (characters or strings). |
| * (For characters only, this is like while contains(current)==true). |
| * <p> |
| * When span() returns, the substring between where it started and the position it returned consists only of set |
| * elements (characters or strings) that are in the set. |
| * <p> |
| * If a set contains strings, then the span will be the longest substring for which there |
| * exists at least one non-overlapping concatenation of set elements (characters or strings). |
| * This is equivalent to a POSIX regular expression for <code>(OR of each set element)*</code>. |
| * (Java/ICU/Perl regex stops at the first match of an OR.) |
| * |
| * @stable ICU 4.4 |
| */ |
| CONTAINED, |
| |
| /** |
| * Continues a span() while there is a set element at the current position. |
| * Increments by the longest matching element at each position. |
| * (For characters only, this is like while contains(current)==true). |
| * <p> |
| * When span() returns, the substring between where it started and the position it returned consists only of set |
| * elements (characters or strings) that are in the set. |
| * <p> |
| * If a set only contains single characters, then this is the same as CONTAINED. |
| * <p> |
| * If a set contains strings, then the span will be the longest substring with a match at each position with the |
| * longest single set element (character or string). |
| * <p> |
| * Use this span condition together with other longest-match algorithms, such as ICU converters |
| * (ucnv_getUnicodeSet()). |
| * |
| * @stable ICU 4.4 |
| */ |
| SIMPLE, |
| } |
| |
| } |