magnetplugin.java

这是一个基于java编写的torrent的P2P源码

					public void
					UIAttached(
						UIInstance		instance )
					{
						if ( instance instanceof UISWTInstance ){
							
							UISWTInstance	swt = (UISWTInstance)instance;
							
							Image	image = swt.loadImage( "com/aelitis/azureus/plugins/magnet/icons/magnet.gif" );

							menu1.setGraphic( swt.createGraphic( image ));
							menu2.setGraphic( swt.createGraphic( image ));							
						}
					}
					
					public void
					UIDetached(
						UIInstance		instance )
					{
						
					}
				});
	}
	
	public URL
	getMagnetURL(
		Download		d )
	{
		Torrent	torrent = d.getTorrent();
		
		if ( torrent == null ){
			
			return( null );
		}
		
		return( getMagnetURL( torrent.getHash()));
	}
	
	public URL
	getMagnetURL(
		byte[]		hash )
	{
		try{
			return( new URL( "magnet:?xt=urn:btih:" + Base32.encode(hash)));
		
		}catch( Throwable e ){
		
			Debug.printStackTrace(e);
		
			return( null );
		}
	}
	
	public byte[]
	badge()
	{
		return( null );
	}
	
	public byte[]
	download(
		final MagnetPluginProgressListener		listener,
		final byte[]							hash,
		final InetSocketAddress[]				sources,
		final long								timeout )
	
		throws MagnetURIHandlerException
	{
		try{
			listener.reportActivity( getMessageText( "report.waiting_ddb" ));

			final DistributedDatabase db = plugin_interface.getDistributedDatabase();
			
			final List			potential_contacts 		= new ArrayList();
			final AESemaphore	potential_contacts_sem 	= new AESemaphore( "MagnetPlugin:liveones" );
			final AEMonitor		potential_contacts_mon	= new AEMonitor( "MagnetPlugin:liveones" );
			
			final int[]			outstanding		= {0};

			listener.reportActivity(  getMessageText( "report.searching" ));
			
			DistributedDatabaseListener	ddb_listener = 
				new DistributedDatabaseListener()
				{
					public void
					event(
						DistributedDatabaseEvent 		event )
					{
						int	type = event.getType();
	
						if ( type == DistributedDatabaseEvent.ET_VALUE_READ ){
													
							contactFound( event.getValue().getContact());
			
						}else if (	type == DistributedDatabaseEvent.ET_OPERATION_COMPLETE ||
									type == DistributedDatabaseEvent.ET_OPERATION_TIMEOUT ){
								
								// now inject any explicit sources
							
							for (int i=0;i<sources.length;i++){
								
								try{
									contactFound( db.importContact(sources[i]));
									
								}catch( Throwable e ){
									
									Debug.printStackTrace(e);
								}
							}
							
							potential_contacts_sem.release();
						}
					}
					
					public void
					contactFound(
						final DistributedDatabaseContact	contact )
					{
						listener.reportActivity( getMessageText( "report.found", contact.getName()));
				
						outstanding[0]++;
						
						Thread t = 
							new AEThread( "MagnetPlugin:HitHandler")
							{
								public void
								runSupport()
								{
									try{
										boolean	alive = contact.isAlive(20*1000);
																						
										listener.reportActivity( 
												getMessageText( alive?"report.alive":"report.dead",	contact.getName()));
										
										try{
											potential_contacts_mon.enter();
											
											Object[]	entry = new Object[]{ new Boolean( alive ), contact};
											
											boolean	added = false;
											
											if ( alive ){
												
													// try and place before first dead entry 
										
												for (int i=0;i<potential_contacts.size();i++){
													
													if (!((Boolean)((Object[])potential_contacts.get(i))[0]).booleanValue()){
														
														potential_contacts.add(i, entry );
														
														added = true;
														
														break;
													}
												}
											}
											
											if ( !added ){
												
												potential_contacts.add( entry );	// dead at end
											}
												
											potential_contacts_sem.release();
												
										}finally{
												
											potential_contacts_mon.exit();
										}
									}finally{
										
										try{
											potential_contacts_mon.enter();													

											outstanding[0]--;
											
										}finally{
											
											potential_contacts_mon.exit();
										}
									}
								}
							};
							
						t.setDaemon(true);
						
						t.start();
					}
				};
				
			db.read(
				ddb_listener,
				db.createKey( hash, "Torrent download lookup for '" + ByteFormatter.encodeString( hash ) + "'" ),
				timeout,
				DistributedDatabase.OP_EXHAUSTIVE_READ | DistributedDatabase.OP_PRIORITY_HIGH );
			
			long	remaining	= timeout;
			
			while( remaining > 0 ){
					
				long start = SystemTime.getCurrentTime();
				
				potential_contacts_sem.reserve( remaining );
				
				remaining -= ( SystemTime.getCurrentTime() - start );
				
				DistributedDatabaseContact	contact;
				boolean						live_contact;
				
				try{
					potential_contacts_mon.enter();
					
					if ( potential_contacts.size() == 0 ){
						
						if ( outstanding[0] == 0 ){
						
							break;
							
						}else{
							
							continue;
						}
					}else{
					
						Object[]	entry = (Object[])potential_contacts.remove(0);
						
						live_contact 	= ((Boolean)entry[0]).booleanValue(); 
						contact 		= (DistributedDatabaseContact)entry[1];
					}
					
				}finally{
					
					potential_contacts_mon.exit();
				}
					
				// System.out.println( "magnetDownload: " + contact.getName() + ", live = " + live_contact );
				
				if ( !live_contact ){
					
					listener.reportActivity( getMessageText( "report.tunnel", contact.getName()));

					contact.openTunnel();
				}
				
				try{
					listener.reportActivity( getMessageText( "report.downloading", contact.getName()));
					
					DistributedDatabaseValue	value = 
						contact.read( 
								new DistributedDatabaseProgressListener()
								{
									public void
									reportSize(
										long	size )
									{
										listener.reportSize( size );
									}
									public void
									reportActivity(
										String	str )
									{
										listener.reportActivity( str );
									}
									
									public void
									reportCompleteness(
										int		percent )
									{
										listener.reportCompleteness( percent );
									}
								},
								db.getStandardTransferType( DistributedDatabaseTransferType.ST_TORRENT ),
								db.createKey ( hash , "Torrent download content for '" + ByteFormatter.encodeString( hash ) + "'"),
								timeout );
										
					if ( value != null ){
						
						return( (byte[])value.getValue(byte[].class));
					}
				}catch( Throwable e ){
					
					listener.reportActivity( getMessageText( "report.error", Debug.getNestedExceptionMessage(e)));
					
					Debug.printStackTrace(e);
				}
			}
		
			return( null );		// nothing found
			
		}catch( Throwable e ){
			
			Debug.printStackTrace(e);
			
			listener.reportActivity( getMessageText( "report.error", Debug.getNestedExceptionMessage(e)));

			throw( new MagnetURIHandlerException( "MagnetURIHandler failed", e ));
		}
	}
	
	protected String
	getMessageText(
		String	resource )
	{
		return( plugin_interface.getUtilities().getLocaleUtilities().getLocalisedMessageText( "MagnetPlugin." + resource ));
	}
	
	protected String
	getMessageText(
		String	resource,
		String	param )
	{
		return( plugin_interface.getUtilities().getLocaleUtilities().getLocalisedMessageText( 
				"MagnetPlugin." + resource, new String[]{ param }));
	}
}