view java/src/uk/ac/qmul/eecs/ccmi/checkboxtree/XMLHandler.java @ 8:ea7885bd9bff tip

fixed bug : render solid line as dotted/dashed when moving the stylus from dotted/dashed to solid

/*  
 CCmI Editor - A Collaborative Cross-Modal Diagram Editing Tool
  
 Copyright (C) 2011  Queen Mary University of London (http://ccmi.eecs.qmul.ac.uk/)

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program 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 for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package uk.ac.qmul.eecs.ccmi.checkboxtree;

import java.util.Stack;

import javax.swing.tree.DefaultTreeModel;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/* Build a tree out of an XML file. The hierarchical structure of the XML file reflects 
 * the structure of the tree. The XMl file must have the form specified in CheckBoxTree
 * class comment.  
 *
 */
class XMLHandler extends DefaultHandler {
	
	@SuppressWarnings("serial")
	public XMLHandler(DefaultTreeModel treeModel, SetProperties properties){
		this.properties = properties;
		this.treeModel = treeModel;
		/* path is used to keep track of the current node's path. If the path is present as a          *      
		 * properties entry, then the current node, that has jus been created, will be set as selected */
		path = new Stack<String>() {
			@Override
			public String toString(){
				StringBuilder builder = new StringBuilder();
				for(int i=0; i<size();i++){
					builder.append(get(i));
					if(i != size()-1)
						builder.append(CheckBoxTreeNode.STRING_PATH_SEPARATOR);
				}
				return builder.toString();
			}
		};
	}

	/*
	 * Create a CheckBoxTreeNode out of an xml tag. The tree node name is given by the value 
	 * attribute. Whether the tree node is selectable or not, depends on the tag name, which can be 
	 * selectable/unselectable. If the node is selectable, then it will be set as selected if its path 
	 * is present in the properties  
	 */
	@Override
	public void startElement(String uri,
            String localName,
            String qName,
            Attributes attributes)
     throws SAXException {
		String nodeName = attributes.getValue(VALUE_ATTR);
		if(nodeName == null)
			throw new SAXException("Value attribute missing");
		boolean isSelectable = SELECTABLE_NODE.equals(qName);
		
		CheckBoxTreeNode newNode = new CheckBoxTreeNode(nodeName,isSelectable);
		if(currentNode == null){
			currentNode = newNode;
			treeModel.setRoot(newNode);
		}else{
			currentNode.add(newNode);
		}
		currentNode = newNode;
		path.push(nodeName);
		if(properties.contains(path.toString()))
			newNode.setSelected(true);
	}
	
	/* when an end tag is encountered, we carry on building the tree with the father as current node */
	@Override
	public void endElement(String uri,
            String localName,
            String qName)
     throws SAXException {
		path.pop();
		currentNode = (CheckBoxTreeNode)currentNode.getParent();
	}

	private CheckBoxTreeNode currentNode;
	private DefaultTreeModel treeModel;
	private SetProperties properties;
	private Stack<String> path;
	/* attributes used in the XML file */
	public static final String VALUE_ATTR = "value";
	public static final String SELECTABLE_NODE = "selectable";
	public static final String UNSELECTABLE_NODE = "selectable";
	
	
}