duke@1: /*
duke@1:  * Copyright 2003 Sun Microsystems, Inc.  All Rights Reserved.
duke@1:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1:  *
duke@1:  * This code is free software; you can redistribute it and/or modify it
duke@1:  * under the terms of the GNU General Public License version 2 only, as
duke@1:  * published by the Free Software Foundation.  Sun designates this
duke@1:  * particular file as subject to the "Classpath" exception as provided
duke@1:  * by Sun in the LICENSE file that accompanied this code.
duke@1:  *
duke@1:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@1:  * version 2 for more details (a copy is included in the LICENSE file that
duke@1:  * accompanied this code).
duke@1:  *
duke@1:  * You should have received a copy of the GNU General Public License version
duke@1:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@1:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1:  *
duke@1:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@1:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@1:  * have any questions.
duke@1:  */
duke@1: package com.sun.tools.doclets.internal.toolkit.builders;
duke@1: 
duke@1: import com.sun.tools.doclets.internal.toolkit.*;
duke@1: import com.sun.tools.doclets.internal.toolkit.util.*;
duke@1: import java.io.*;
duke@1: import java.util.*;
duke@1: import org.xml.sax.*;
duke@1: import org.xml.sax.helpers.DefaultHandler;
duke@1: import javax.xml.parsers.*;
duke@1: 
duke@1: /**
duke@1:  * Parse the XML that specified the order of operation for the builders.  This
duke@1:  * Parser uses SAX parsing.
duke@1:  *
duke@1:  * @author Jamie Ho
duke@1:  * @since 1.5
duke@1:  * @see SAXParser
duke@1:  */
duke@1: public class LayoutParser extends DefaultHandler {
duke@1: 
duke@1:     /**
duke@1:      * The map of XML elements that have been parsed.
duke@1:      */
duke@1:     private Map xmlElementsMap;
duke@1: 
duke@1:     private Configuration configuration;
duke@1:     private static LayoutParser instance;
duke@1:     private String currentRoot;
duke@1:     private boolean isParsing;
duke@1: 
duke@1:     /**
duke@1:      * This class is a singleton.
duke@1:      */
duke@1:     private LayoutParser(Configuration configuration) {
duke@1:         xmlElementsMap = new HashMap();
duke@1:         this.configuration = configuration;
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Return an instance of the BuilderXML.
duke@1:      *
duke@1:      * @param configuration the current configuration of the doclet.
duke@1:      * @return an instance of the BuilderXML.
duke@1:      */
duke@1:     public static LayoutParser getInstance(Configuration configuration) {
duke@1:         if (instance == null) {
duke@1:             instance = new LayoutParser(configuration);
duke@1:         }
duke@1:         return instance;
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Parse the XML specifying the layout of the documentation.
duke@1:      *
duke@1:      * @return List the list of XML elements parsed.
duke@1:      */
duke@1:     public List parseXML(String root) {
duke@1:         if (xmlElementsMap.containsKey(root)) {
duke@1:             return (List) xmlElementsMap.get(root);
duke@1:         }
duke@1:         try {
duke@1:             List xmlElements = new ArrayList();
duke@1:             xmlElementsMap.put(root, xmlElements);
duke@1:             currentRoot = root;
duke@1:             isParsing = false;
duke@1:             SAXParserFactory factory = SAXParserFactory.newInstance();
duke@1:             SAXParser saxParser = factory.newSAXParser();
duke@1:             InputStream in = configuration.getBuilderXML();
duke@1:             saxParser.parse(in, this);
duke@1:             return xmlElements;
duke@1:         } catch (Throwable t) {
duke@1:             t.printStackTrace();
duke@1:             throw new DocletAbortException();
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * {@inheritDoc}
duke@1:      */
duke@1:     public void startElement(String namespaceURI, String sName, String qName,
duke@1:         Attributes attrs)
duke@1:     throws SAXException {
duke@1:         if (isParsing || qName.equals(currentRoot)) {
duke@1:             isParsing = true;
duke@1:             List xmlElements = (List) xmlElementsMap.get(currentRoot);
duke@1:             xmlElements.add(qName);
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * {@inheritDoc}
duke@1:      */
duke@1:     public void endElement(String namespaceURI, String sName, String qName)
duke@1:     throws SAXException {
duke@1:         if (! isParsing) {
duke@1:             isParsing = false;
duke@1:             return;
duke@1:         }
duke@1:         List xmlElements = (List) xmlElementsMap.get(currentRoot);
duke@1:         if (xmlElements.get(xmlElements.size()-1).equals(qName)) {
duke@1:             return;
duke@1:         } else {
duke@1:             List subElements = new ArrayList();
duke@1:             int targetIndex = xmlElements.indexOf(qName);
duke@1:             int size = xmlElements.size();
duke@1:             for (int i = targetIndex; i < size; i++) {
duke@1:                 subElements.add(xmlElements.get(targetIndex));
duke@1:                 xmlElements.remove(targetIndex);
duke@1:             }
duke@1:             //Save the sub elements as a list.
duke@1:             xmlElements.add(subElements);
duke@1:         }
duke@1:         isParsing = ! qName.equals(currentRoot);
duke@1:     }
duke@1: }