1   /*   Copyright 2004 The Apache Software Foundation
    2    *
    3    *   Licensed under the Apache License, Version 2.0 (the "License");
    4    *   you may not use this file except in compliance with the License.
    5    *   You may obtain a copy of the License at
    6    *
    7    *       http://www.apache.org/licenses/LICENSE-2.0
    8    *
    9    *   Unless required by applicable law or agreed to in writing, software
   10    *   distributed under the License is distributed on an "AS IS" BASIS,
   11    *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   12    *   See the License for the specific language governing permissions and
   13    *  limitations under the License.
   14    */
   15   
   16   package org.apache.xmlbeans.samples.xmltree;
   17   
   18   import org.apache.xmlbeans.XmlException;
   19   import org.apache.xmlbeans.XmlObject;
   20   
   21   import javax.swing.ImageIcon;
   22   import javax.swing.JTree;
   23   import javax.swing.tree.DefaultTreeCellRenderer;
   24   import javax.swing.tree.TreeSelectionModel;
   25   import java.io.File;
   26   import java.io.IOException;
   27   import java.net.MalformedURLException;
   28   import java.net.URL;
   29   
   30   /**
   31    * A tree view on XML, with nodes representing both elements and attributes. See
   32    * {@link XmlEntry}and {@link XmlModel}for information on how information
   33    * about the underlying XML is retrieved for use in the tree. Those classes use
   34    * XMLBeans to provide a wrapper by which the tree exposes the underlying XML.
   35    */
   36   final class XmlTree extends JTree
   37   {
   38       /**
   39        * Receives <root> XML instance, executing methods that 
   40        * edit the received instance or create a new one.
   41        * 
   42        * @param args An array in which the first item is a
   43        * path to the XML instance file.
   44        */
   45       public static void main(String[] args)
   46       {
   47           System.out.println("Creating XmlTree.\n");
   48           File xmlFile = new File(args[0]);
   49           XmlTreeFrame thisSample = new XmlTreeFrame(xmlFile);
   50       }
   51       
   52       /**
   53        * Constructs the tree using <em>xmlFile</em> as an original source of
   54        * nodes.
   55        * 
   56        * @param xmlFile The XML file the new tree should represent.
   57        */
   58       public XmlTree(File xmlFile)
   59       {
   60           setXmlFile(xmlFile);
   61       }
   62   
   63       /**
   64        * Sets the XML file that should be used to build the tree; the tree will be
   65        * refreshed to represent <em>xmlFile</em>.
   66        * 
   67        * @param xmlFile The XML file the new tree should represent.
   68        */
   69       public void setXmlFile(File xmlFile)
   70       {
   71           initComponents(xmlFile);
   72       }
   73   
   74       /**
   75        * Parses <em>xmlFile</em> into XMLBeans types (XmlObject instances),
   76        * returning the instance representing the root.
   77        * 
   78        * @param xmlFile The XML file to parse.
   79        * @return An XmlObject representing the root of the parsed XML.
   80        */
   81       private static XmlObject parseXml(File xmlFile)
   82       {
   83           XmlObject xml = XmlObject.Factory.newInstance();
   84           try
   85           {
   86               xml = XmlObject.Factory.parse(xmlFile);
   87           } catch (XmlException xmle)
   88           {
   89               System.err.println(xmle.toString());
   90           } catch (IOException ioe)
   91           {
   92               System.err.println(ioe.toString());
   93           }
   94           return xml;
   95       }
   96   
   97       /**
   98        * Sets up the components that make up this tree.
   99        * 
  100        * @param xmlFile The XML file the new tree should represent.
  101        */
  102       private void initComponents(File xmlFile)
  103       {
  104           // Parse the XML create an XmlModel from its root.
  105           XmlEntry rootEntry = new XmlEntry(parseXml(xmlFile));
  106           XmlModel treemodel = new XmlModel(rootEntry);
  107   
  108           // Set UI properties.
  109           setModel(treemodel);
  110           setRootVisible(true);
  111           setShowsRootHandles(true);
  112           setAutoscrolls(true);
  113           setEditable(false);
  114           getSelectionModel().setSelectionMode(
  115                   TreeSelectionModel.SINGLE_TREE_SELECTION);
  116           DefaultTreeCellRenderer renderer = new DefaultTreeCellRenderer();
  117           // Uncomment these lines to provide your own GIF files for
  118           // tree icons.
  119           //        renderer.setLeafIcon(createImageIcon("images/leaf.gif"));
  120           //        renderer.setOpenIcon(createImageIcon("images/minus.gif"));
  121           //        renderer.setClosedIcon(createImageIcon("images/plus.gif"));
  122           setCellRenderer(renderer);
  123           setRootVisible(false);
  124           setAutoscrolls(false);
  125       }
  126   
  127       /**
  128        * Creates an icon from a path that points at a GIF file. This method is
  129        * called to create tree node icons.
  130        * 
  131        * @param path The path to a GIF file.
  132        * @return An icon instance.
  133        */
  134       private static ImageIcon createImageIcon(String path)
  135       {
  136           File imgFile = new File(path);
  137           URL imgUrl = null;
  138           try
  139           {
  140               imgUrl = imgFile.toURL();
  141           } catch (MalformedURLException e)
  142           {
  143               e.printStackTrace();
  144           }
  145           if (imgUrl != null)
  146           {
  147               return new ImageIcon(imgUrl);
  148           } else
  149           {
  150               System.err.println("Couldn't find file: " + path);
  151               return null;
  152           }
  153       }
  154   }