rdvstatus.java

有关java 的p2p应用,是一般很好的教程,有兴趣的朋友应该好好阅读一下

/*
 *  Copyright (c) 2001 Sun Microsystems, Inc.  All rights
 *  reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *  2. Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following disclaimer in
 *  the documentation and/or other materials provided with the
 *  distribution.
 *
 *  3. The end-user documentation included with the redistribution,
 *  if any, must include the following acknowledgment:
 *  "This product includes software developed by the
 *  Sun Microsystems, Inc. for Project JXTA."
 *  Alternately, this acknowledgment may appear in the software itself,
 *  if and wherever such third-party acknowledgments normally appear.
 *
 *  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
 *  not be used to endorse or promote products derived from this
 *  software without prior written permission. For written
 *  permission, please contact Project JXTA at http://www.jxta.org.
 *
 *  5. Products derived from this software may not be called "JXTA",
 *  nor may "JXTA" appear in their name, without prior written
 *  permission of Sun.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED.  IN NO EVENT SHALL SUN MICROSYSTEMS OR
 *  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 *  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 *  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *  ====================================================================
 *
 *  This software consists of voluntary contributions made by many
 *  individuals on behalf of Project JXTA.  For more
 *  information on Project JXTA, please see
 *  <http://www.jxta.org/>.
 *
 *  This license is based on the BSD license adopted by the Apache Foundation.
 *
 *  $Id: rdvstatus.java,v 1.23 2005/12/15 00:53:22 bondolo Exp $
 */
package net.jxta.impl.shell.bin.rdvstatus;

import java.io.*;
import java.util.*;

import net.jxta.discovery.DiscoveryService;
import net.jxta.peergroup.PeerGroupID;
import net.jxta.impl.shell.*;
import net.jxta.peer.*;
import net.jxta.id.*;
import net.jxta.protocol.PeerAdvertisement;
import net.jxta.protocol.PeerGroupAdvertisement;
import net.jxta.rendezvous.*;
import net.jxta.util.*;

import net.jxta.impl.rendezvous.RendezVousServiceInterface;
import net.jxta.impl.rendezvous.rpv.PeerView;
import net.jxta.impl.rendezvous.rpv.PeerViewElement;

/**
 *  Display information about the rendezvous service.
 */
public class rdvstatus extends ShellApp {
    DiscoveryService discovery;
    
    Map names = new HashMap();
    
    /**
     *  {@inheritDoc}
     **/
    public int startApp( String[] args ) {
        
        boolean verbose = false;
        
        GetOpt options = new GetOpt( args, 0, "v" );
        
        while( true ) {
            int option;
            try {
                option = options.getNextOption();
            } catch( IllegalArgumentException badopt ) {
                consoleMessage( "Illegal argument :" + badopt );
                return syntaxError();
            }
                        
            if( -1 == option ) {
                break;
            }
            
            switch( option ) {
                
                case 'v' :
                    verbose = true;
                    break;
                    
                default :
                    consoleMessage( "Unrecognized option" );
                    return syntaxError();
            }
        }
        
        if( null != options.getNextParameter() ) {
            consoleMessage( "Unexpected parameter." );
            return syntaxError();
        }
        
        RendezVousService rdv = getGroup().getRendezVousService();
        
        if( null == rdv ) {
            consoleMessage( "No Rendezvous Service in group " );
            return ShellApp.appMiscError;
        }
        
        discovery = getGroup().getDiscoveryService();
        
        println( " " );
        println( "Rendezvous Status: " );
        println( "__________________" );
        println( " " );
        
        println( "Current configuration : " + rdv.getRendezVousStatus() );
        
        RendezVousServiceInterface stdRdv = null;
        net.jxta.impl.rendezvous.StdRendezVousService stdRdvProvider = null;
        if( rdv instanceof net.jxta.impl.rendezvous.RendezVousServiceInterface ) {
            stdRdv = (RendezVousServiceInterface) rdv;
            
            if( null != stdRdv ) {
                net.jxta.impl.rendezvous.RendezVousServiceProvider provider = stdRdv.getRendezvousProvider();
                
                if( provider instanceof net.jxta.impl.rendezvous.StdRendezVousService ) {
                    stdRdvProvider = (net.jxta.impl.rendezvous.StdRendezVousService) provider;
                }
            }
            
            PeerView rpv = stdRdv.getPeerView();
            PeerViewElement self = rpv.getSelf();
            if( verbose ) {
                print( "\t" + self.getRdvAdvertisement().getPeerID() );
            }
            println( "\t" + self );
            
            PeerViewElement pves[] = (PeerViewElement[]) rpv.getView().toArray( new PeerViewElement[0] );
            
            println( " " );
            println( "Peer View : " );
            if( pves.length > 0 ) {
                for( int eachPVE = pves.length -1; eachPVE >= 0; eachPVE-- ) {
                    if( verbose ) {
                        print( "\t" + pves[eachPVE].getRdvAdvertisement().getPeerID() );
                    }
                    print( "\t" + pves[eachPVE] );
                    
                    if( rdv.isRendezVous() ) {
                        if( pves[eachPVE] == rpv.getUpPeer() ) {
                            println( "\t(UP)" );
                        } else if( pves[eachPVE] == rpv.getDownPeer() ) {
                            println( "\t(DOWN)" );
                        } else {
                            println( "" );
                        }
                    } else {
                        println( "" );
                    }
                }
            } else {
                println( "\t[None]" );
            }
        }
        println( " " );
        
        if( !rdv.isRendezVous() ) {
            Enumeration rdvs = rdv.getConnectedRendezVous();
            
            println( "Rendezvous Connections :" );
            if ( !rdvs.hasMoreElements() ) {
                println( "\t[None]" );
                
            } else {
                while ( rdvs.hasMoreElements() ) {
                    try {
                        ID connection = (PeerID) rdvs.nextElement();
                        if( verbose ) {
                            print( "\t" + connection );
                        }
                        if( null != stdRdvProvider ) {
                            println( "\t" + stdRdvProvider.getPeerConnection( connection ) );
                        } else {
                            String peerName = idToName( connection );
                            println( "\t" + peerName );
                        }
                    } catch ( Exception e ) {
                        printStackTrace( "failed", e );
                    }
                }
            }
            println( " " );
            
            Enumeration rmRdvs = rdv.getDisconnectedRendezVous();
            
            println( "Rendezvous Disconnections :" );
            if ( !rmRdvs.hasMoreElements() ) {
                println( "\t[None]" );
            } else {
                while ( rmRdvs.hasMoreElements() ) {
                    try {
                        ID connection = (PeerID) rmRdvs.nextElement();
                        print( "\t" );
                        if( verbose ) {
                            print( "\t" + connection );
                        }
                        String peerName = idToName( connection );
                        println( "\t" + peerName );
                    } catch ( Exception e ) {
                        printStackTrace( "failed", e );
                    }
                }
                
            }
            println( " " );
        }
        
        // no need to display clients if the peer is not a rendezvous for
        // the group
        if( rdv.isRendezVous() ) {
            
            Enumeration clients = rdv.getConnectedPeers();
            
            println( "Rendezvous Client Connections :" );
            if ( !clients.hasMoreElements() ) {
                println( "\t[None]" );
                
            } else {
                while ( clients.hasMoreElements() ) {
                    try {
                        ID connection = (PeerID) clients.nextElement();
                        if( verbose ) {
                            print( "\t" + connection );
                        }
                        if( null != stdRdvProvider ) {
                            println( "\t" + stdRdvProvider.getPeerConnection( connection ) );
                        } else {
                            String peerName = idToName( connection );
                            println( "\t" + peerName );
                        }
                    } catch ( Exception e ) {
                        println( "failed with " + e );
                    }
                }
            }
            println( " " );
        }
        
        return ShellApp.appNoError;
    }
    
    private int syntaxError() {
        consoleMessage( "usage : rdvstatus [-v] " );
        return ShellApp.appParamError;
    }
    
    /**
     * {@inheritDoc}
     */
    public String getDescription() {
        return "Display information about the rendezvous service";
    }
    
    /**
     * {@inheritDoc}
     */
    public void help() {
        println( "NAME" );
        println( "     rdvstatus - " + getDescription() );
        println( " " );
        println( "SYNOPSIS" );
        println( "     rdvstatus [-v]" );
        println( " " );
        println( "OPTIONS" );
        println( "     [-v]    print verbose information" );
        println( " " );
        println( "DESCRIPTION" );
        println( " " );
        println( "'rdvstatus' displays information about the rendezvous" );
        println( "service in the current group. The command shows the current" );
        println( "peerview and any rendezvous or client connections." );
        println( "" );
        println( "EXAMPLE" );
        println( " " );
        println( "    JXTA>rdvstatus" );
        println( " " );
        println( " " );
        println( "SEE ALSO" );
        println( "    whoami peers" );
    }
    
    
    /**
     *  Description of the Method
     *
     *@param  id  Description of Parameter
     *@return     Description of the Returned Value
     */
    private String idToName( ID id ) {
        
        String idstring = id.toString();
        String name = (String) names.get( id );
        
        if( null != name ) {
            return name;
        }
        
        try {
            Enumeration res;
            
            if( id instanceof PeerID ) {
                res = discovery.getLocalAdvertisements( DiscoveryService.PEER, "PID", idstring );
                
                if( res.hasMoreElements() ) {
                    name = ((PeerAdvertisement)res.nextElement()).getName();
                }
            } else if( id instanceof PeerGroupID ) {
                res = discovery.getLocalAdvertisements( DiscoveryService.GROUP, "GID", idstring );
                
                if( res.hasMoreElements() ) {
                    name = ((PeerGroupAdvertisement)res.nextElement()).getName();
                }
            }
        } catch( IOException failed ) {
        }
        
        if( null != name ) {
            names.put( id, name );
        } else {
            name = "[unknown]";
        }
        
        return name;
    }
}