| /* |
| * Copyright (c) 1998, 2014, 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 javax.swing.text.html.parser; |
| |
| import java.util.Vector; |
| import java.util.Enumeration; |
| import java.io.*; |
| |
| |
| /** |
| * A representation of a content model. A content model is |
| * basically a restricted BNF expression. It is restricted in |
| * the sense that it must be deterministic. This means that you |
| * don't have to represent it as a finite state automaton.<p> |
| * See Annex H on page 556 of the SGML handbook for more information. |
| * |
| * @author Arthur van Hoff |
| * |
| */ |
| @SuppressWarnings("serial") // Same-version serialization only |
| public final class ContentModel implements Serializable { |
| /** |
| * Type. Either '*', '?', '+', ',', '|', '&'. |
| */ |
| public int type; |
| |
| /** |
| * The content. Either an Element or a ContentModel. |
| */ |
| public Object content; |
| |
| /** |
| * The next content model (in a ',', '|' or '&' expression). |
| */ |
| public ContentModel next; |
| |
| /** |
| * Creates {@code ContentModel} |
| */ |
| public ContentModel() { |
| } |
| |
| /** |
| * Create a content model for an element. |
| * |
| * @param content the element |
| */ |
| public ContentModel(Element content) { |
| this(0, content, null); |
| } |
| |
| /** |
| * Create a content model of a particular type. |
| * |
| * @param type the type |
| * @param content the content |
| */ |
| public ContentModel(int type, ContentModel content) { |
| this(type, content, null); |
| } |
| |
| /** |
| * Create a content model of a particular type. |
| * |
| * @param type the type |
| * @param content the content |
| * @param next the next content model |
| */ |
| public ContentModel(int type, Object content, ContentModel next) { |
| this.type = type; |
| this.content = content; |
| this.next = next; |
| } |
| |
| /** |
| * Return true if the content model could |
| * match an empty input stream. |
| * |
| * @return {@code true} if the content model could |
| * match an empty input stream |
| */ |
| public boolean empty() { |
| switch (type) { |
| case '*': |
| case '?': |
| return true; |
| |
| case '+': |
| case '|': |
| for (ContentModel m = (ContentModel)content ; m != null ; m = m.next) { |
| if (m.empty()) { |
| return true; |
| } |
| } |
| return false; |
| |
| case ',': |
| case '&': |
| for (ContentModel m = (ContentModel)content ; m != null ; m = m.next) { |
| if (!m.empty()) { |
| return false; |
| } |
| } |
| return true; |
| |
| default: |
| return false; |
| } |
| } |
| |
| /** |
| * Update elemVec with the list of elements that are |
| * part of the this contentModel. |
| * |
| * @param elemVec the list of elements |
| */ |
| public void getElements(Vector<Element> elemVec) { |
| switch (type) { |
| case '*': |
| case '?': |
| case '+': |
| ((ContentModel)content).getElements(elemVec); |
| break; |
| case ',': |
| case '|': |
| case '&': |
| for (ContentModel m=(ContentModel)content; m != null; m=m.next){ |
| m.getElements(elemVec); |
| } |
| break; |
| default: |
| elemVec.addElement((Element)content); |
| } |
| } |
| |
| private boolean valSet[]; |
| private boolean val[]; |
| // A cache used by first(). This cache was found to speed parsing |
| // by about 10% (based on measurements of the 4-12 code base after |
| // buffering was fixed). |
| |
| /** |
| * Return true if the token could potentially be the |
| * first token in the input stream. |
| * |
| * @param token the token |
| * |
| * @return {@code true} if the token could potentially be the first token |
| * in the input stream |
| */ |
| public boolean first(Object token) { |
| switch (type) { |
| case '*': |
| case '?': |
| case '+': |
| return ((ContentModel)content).first(token); |
| |
| case ',': |
| for (ContentModel m = (ContentModel)content ; m != null ; m = m.next) { |
| if (m.first(token)) { |
| return true; |
| } |
| if (!m.empty()) { |
| return false; |
| } |
| } |
| return false; |
| |
| case '|': |
| case '&': { |
| Element e = (Element) token; |
| if (valSet == null || valSet.length <= Element.getMaxIndex()) { |
| valSet = new boolean[Element.getMaxIndex() + 1]; |
| val = new boolean[valSet.length]; |
| } |
| if (valSet[e.index]) { |
| return val[e.index]; |
| } |
| for (ContentModel m = (ContentModel)content ; m != null ; m = m.next) { |
| if (m.first(token)) { |
| val[e.index] = true; |
| break; |
| } |
| } |
| valSet[e.index] = true; |
| return val[e.index]; |
| } |
| |
| default: |
| return (content == token); |
| // PENDING: refer to comment in ContentModelState |
| /* |
| if (content == token) { |
| return true; |
| } |
| Element e = (Element)content; |
| if (e.omitStart() && e.content != null) { |
| return e.content.first(token); |
| } |
| return false; |
| */ |
| } |
| } |
| |
| /** |
| * Return the element that must be next. |
| * |
| * @return the element that must be next |
| */ |
| public Element first() { |
| switch (type) { |
| case '&': |
| case '|': |
| case '*': |
| case '?': |
| return null; |
| |
| case '+': |
| case ',': |
| return ((ContentModel)content).first(); |
| |
| default: |
| return (Element)content; |
| } |
| } |
| |
| /** |
| * Convert to a string. |
| * |
| * @return the string representation of this {@code ContentModel} |
| */ |
| public String toString() { |
| switch (type) { |
| case '*': |
| return content + "*"; |
| case '?': |
| return content + "?"; |
| case '+': |
| return content + "+"; |
| |
| case ',': |
| case '|': |
| case '&': |
| char data[] = {' ', (char)type, ' '}; |
| String str = ""; |
| for (ContentModel m = (ContentModel)content ; m != null ; m = m.next) { |
| str = str + m; |
| if (m.next != null) { |
| str += new String(data); |
| } |
| } |
| return "(" + str + ")"; |
| |
| default: |
| return content.toString(); |
| } |
| } |
| } |