001 /*
002 * Copyright 2003-2008 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025 package com.sun.tools.doclets.internal.toolkit.builders;
026
027 import com.sun.tools.doclets.internal.toolkit.*;
028 import com.sun.tools.doclets.internal.toolkit.util.*;
029 import java.io.*;
030 import java.util.*;
031 import org.xml.sax.*;
032 import org.xml.sax.helpers.DefaultHandler;
033 import javax.xml.parsers.*;
034
035 /**
036 * Parse the XML that specified the order of operation for the builders. This
037 * Parser uses SAX parsing.
038 *
039 * @author Jamie Ho
040 * @since 1.5
041 * @see SAXParser
042 */
043 public class LayoutParser extends DefaultHandler {
044
045 /**
046 * The map of XML elements that have been parsed.
047 */
048 private Map<String,List<Object>> xmlElementsMap;
049
050 private Configuration configuration;
051 private static LayoutParser instance;
052 private String currentRoot;
053 private boolean isParsing;
054
055 /**
056 * This class is a singleton.
057 */
058 private LayoutParser(Configuration configuration) {
059 xmlElementsMap = new HashMap<String,List<Object>>();
060 this.configuration = configuration;
061 }
062
063 /**
064 * Return an instance of the BuilderXML.
065 *
066 * @param configuration the current configuration of the doclet.
067 * @return an instance of the BuilderXML.
068 */
069 public static LayoutParser getInstance(Configuration configuration) {
070 if (instance == null) {
071 instance = new LayoutParser(configuration);
072 }
073 return instance;
074 }
075
076 /**
077 * Parse the XML specifying the layout of the documentation.
078 *
079 * @return List the list of XML elements parsed.
080 */
081 public List<?> parseXML(String root) {
082 if (xmlElementsMap.containsKey(root)) {
083 return xmlElementsMap.get(root);
084 }
085 try {
086 List<Object> xmlElements = new ArrayList<Object>();
087 xmlElementsMap.put(root, xmlElements);
088 currentRoot = root;
089 isParsing = false;
090 SAXParserFactory factory = SAXParserFactory.newInstance();
091 SAXParser saxParser = factory.newSAXParser();
092 InputStream in = configuration.getBuilderXML();
093 saxParser.parse(in, this);
094 return xmlElements;
095 } catch (Throwable t) {
096 t.printStackTrace();
097 throw new DocletAbortException();
098 }
099 }
100
101 /**
102 * {@inheritDoc}
103 */
104 public void startElement(String namespaceURI, String sName, String qName,
105 Attributes attrs)
106 throws SAXException {
107 if (isParsing || qName.equals(currentRoot)) {
108 isParsing = true;
109 List<Object> xmlElements = xmlElementsMap.get(currentRoot);
110 xmlElements.add(qName);
111 }
112 }
113
114 /**
115 * {@inheritDoc}
116 */
117 public void endElement(String namespaceURI, String sName, String qName)
118 throws SAXException {
119 if (! isParsing) {
120 isParsing = false;
121 return;
122 }
123 List<Object> xmlElements = xmlElementsMap.get(currentRoot);
124 if (xmlElements.get(xmlElements.size()-1).equals(qName)) {
125 return;
126 } else {
127 List<Object> subElements = new ArrayList<Object>();
128 int targetIndex = xmlElements.indexOf(qName);
129 int size = xmlElements.size();
130 for (int i = targetIndex; i < size; i++) {
131 subElements.add(xmlElements.get(targetIndex));
132 xmlElements.remove(targetIndex);
133 }
134 //Save the sub elements as a list.
135 xmlElements.add(subElements);
136 }
137 isParsing = ! qName.equals(currentRoot);
138 }
139 }