explorer.java

Java p2p程序设计2002年版

/*
 * Explorer.java
 * @Author Daniel Brookshier [e-mail]
 *
 * Created on December 20, 2001, 10:42 PM
 */

package com.sams.jxta.explorer;
import com.sams.swing.AdvertisementTreeCellRenderer;
import net.jxta.document.Advertisement;
import net.jxta.document.StructuredTextDocument;
import javax.swing.JTree;
import javax.swing.JFrame;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;
import net.jxta.protocol.PeerGroupAdvertisement;
import java.io.IOException;
import java.io.StringWriter;
import net.jxta.peergroup.PeerGroup;
import net.jxta.peergroup.PeerGroupFactory;

import org.apache.log4j.Category;
import java.util.Hashtable;
import javax.swing.JTree.DynamicUtilTreeNode;
import net.jxta.exception.PeerGroupException;



/**
 *
 * @author  Daniel Brookshier [e-mail]
 */
public class Explorer extends JFrame {
    private static final Category LOG =  Category.getInstance(Explorer.class.getName());
    protected PeerGroup netPeerGroup;
    protected TreePath treePath;
    protected JTree.DynamicUtilTreeNode root;
    /** Creates new form Explorer */
    public Explorer() {
        initComponents();
        // Initialize discovery tree
        advrtTree.setCellRenderer(new AdvertisementTreeCellRenderer());
        try{
            netPeerGroup = PeerGroupFactory.newNetPeerGroup();
            root = new JTree.DynamicUtilTreeNode(netPeerGroup,new Hashtable());
            treePath = new TreePath(root);
            ((DefaultTreeModel)advrtTree.getModel()).setRoot(root);
            addGroup((JTree.DynamicUtilTreeNode)root);
        } catch (Exception e) {
            LOG.error("fatal error : group creation failure",e);
            System.exit(-1);
        }
    }
    
    protected void addGroup(JTree.DynamicUtilTreeNode groupNode){
        
        //Advertisement advertisement = (Advertisement)groupNode.getUserObject();
        
        PeerDiscoveryThread peerDiscoveryThread = new PeerDiscoveryThread( advrtTree, netPeerGroup, groupNode);
        Thread discoThread = new Thread(peerDiscoveryThread);
        discoThread.start();
        
        /*
        // Three trials
        int count =0;
        //NullCredential credential = new NullCredential( this, netPeerGroup, peer, "PDA-User" );
        while(count<3 && (groupManager.joinGroup(rootJPDA,null,"NullAuthentication")==null)){
            count++;
        }
         */
    }
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    private void initComponents() {//GEN-BEGIN:initComponents
        pyramidFriendsSplitPane = new javax.swing.JSplitPane();
        treeScrollPane = new javax.swing.JScrollPane();
        advrtTree = new javax.swing.JTree();
        xmlScrollPane = new javax.swing.JScrollPane();
        xmlTextArea = new javax.swing.JTextArea();
        jMenuBar1 = new javax.swing.JMenuBar();
        jMenu1 = new javax.swing.JMenu();
        forceDiscoveryMenuItem = new javax.swing.JMenuItem();
        purgeMenuItem = new javax.swing.JMenuItem();

        setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                exitForm(evt);
            }
        });

        pyramidFriendsSplitPane.setDividerLocation(225);
        treeScrollPane.setBorder(new javax.swing.border.TitledBorder("Advertisements"));
        advrtTree.setFont(new java.awt.Font("Dialog", 0, 10));
        advrtTree.addTreeSelectionListener(new javax.swing.event.TreeSelectionListener() {
            public void valueChanged(javax.swing.event.TreeSelectionEvent evt) {
                advrtTreeValueChanged(evt);
            }
        });

        treeScrollPane.setViewportView(advrtTree);

        pyramidFriendsSplitPane.setLeftComponent(treeScrollPane);

        xmlScrollPane.setViewportBorder(new javax.swing.border.TitledBorder("XML Display"));
        xmlTextArea.setFont(new java.awt.Font("Dialog", 0, 10));
        xmlScrollPane.setViewportView(xmlTextArea);

        pyramidFriendsSplitPane.setRightComponent(xmlScrollPane);

        getContentPane().add(pyramidFriendsSplitPane, java.awt.BorderLayout.CENTER);

        jMenu1.setText("File");
        forceDiscoveryMenuItem.setText("Force Discovery");
        forceDiscoveryMenuItem.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                forceDiscoveryMenuItemActionPerformed(evt);
            }
        });

        jMenu1.add(forceDiscoveryMenuItem);
        purgeMenuItem.setText("Purge Advertisements");
        jMenu1.add(purgeMenuItem);
        jMenuBar1.add(jMenu1);
        setJMenuBar(jMenuBar1);

        pack();
    }//GEN-END:initComponents
    
    private void forceDiscoveryMenuItemActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_forceDiscoveryMenuItemActionPerformed
        // Add your handling code here:
    }//GEN-LAST:event_forceDiscoveryMenuItemActionPerformed
    
    private void advrtTreeValueChanged(javax.swing.event.TreeSelectionEvent evt) {//GEN-FIRST:event_advrtTreeValueChanged
        Object testNode = ((JTree)evt.getSource()).getLastSelectedPathComponent();
        if(testNode == null){
            return;
        }
        // Synchronize the node so that we block further actions.
        synchronized(testNode){
            DefaultMutableTreeNode node = (DefaultMutableTreeNode)testNode;
            Object nodeInfo=null;
            if (node != null) {
                nodeInfo = node.getUserObject();
                // If it is an advertisement, display it.
                if (nodeInfo instanceof Advertisement){
                    Advertisement advertisement = (Advertisement)nodeInfo;
                    String data = getAdvertisementDoc(advertisement);
                    xmlTextArea.setText(data);
                }
            }
            // If it is a group, open it.
            if (nodeInfo instanceof PeerGroupAdvertisement  ){
                if (node.isLeaf() || node.getChildCount() ==0){
                    System.out.println("Opening group");
                    addGroup((JTree.DynamicUtilTreeNode)node);
                }
            }
        }
        //}
    }//GEN-LAST:event_advrtTreeValueChanged
    
    /** Exit the Application */
    private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm
        System.exit(0);
    }//GEN-LAST:event_exitForm
    
    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        new Explorer().show();
    }
    
    
    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JSplitPane pyramidFriendsSplitPane;
    private javax.swing.JMenuItem forceDiscoveryMenuItem;
    private javax.swing.JScrollPane treeScrollPane;
    private javax.swing.JTree advrtTree;
    private javax.swing.JScrollPane xmlScrollPane;
    private javax.swing.JTextArea xmlTextArea;
    private javax.swing.JMenuBar jMenuBar1;
    private javax.swing.JMenu jMenu1;
    private javax.swing.JMenuItem purgeMenuItem;
    // End of variables declaration//GEN-END:variables
    public String getAdvertisementDoc(Advertisement advertisement) {
        
        try {
            
            // display the advertisement as a plain text dcoument.
            net.jxta.document.MimeMediaType type = new net.jxta.document.MimeMediaType("text/xml");
            
            // Convert the advertisement to a document
            StructuredTextDocument doc = (StructuredTextDocument)advertisement.getDocument(type);
            
            // Write the advert text to a string.
            StringWriter out = new StringWriter();
            doc.sendToWriter(out);
            
            //Write the doc to a string.
            String docString = out.toString();
            
            // cleanup the writer.
            out.close();
            
            return docString;
            
        }catch(IOException ioe) {
            ioe.printStackTrace();
            return "Error: IO exception  thrown by StringWriter";
        }catch(Exception jle) {
            jle.printStackTrace();
            return "Error: Exception  thrown by getDocument()";
        }
    }//end of printServiceAdvertisement();
}//end of class Explorer