xferdaemon.java

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/*
 * 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: XferDaemon.java,v 1.13 2004/05/20 00:16:50 bondolo Exp $
 */


package net.jxta.impl.shell.bin.xfer;

import java.io.File;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.Vector;

import java.io.IOException;
import java.lang.reflect.UndeclaredThrowableException;

import net.jxta.discovery.DiscoveryService;
import net.jxta.endpoint.EndpointAddress;
import net.jxta.endpoint.EndpointListener;
import net.jxta.endpoint.EndpointService;
import net.jxta.endpoint.Message;
import net.jxta.endpoint.MessageElement;
import net.jxta.peergroup.PeerGroup;
import net.jxta.pipe.InputPipe;
import net.jxta.pipe.OutputPipe;
import net.jxta.pipe.PipeMsgEvent;
import net.jxta.pipe.PipeMsgListener;
import net.jxta.protocol.PipeAdvertisement;

import net.jxta.impl.shell.ShellApp;
import net.jxta.impl.shell.ShellObject;
import net.jxta.impl.shell.ShellEnv;

/**
 *  send a file from one peer to another. destination may be an endpoint address
 *  or a pipe.
 *
 **/
class XferDaemon extends Thread implements EndpointListener, PipeMsgListener {
    
    private static final String XFERSERVICENAME = "jxtaxfer";
    
    private OutputPipe console;
    
    private volatile boolean closed = false;
    
    private Map incoming = Collections.synchronizedMap( new HashMap() );
    
    private Map outgoing = Collections.synchronizedMap( new HashMap() );
    
    private String userName;
    private PipeAdvertisement adv;
    private PeerGroup group;
    
    private InputPipe pipeIn;
    private boolean endpointListenerRegistered = false;
    
    // Some file stuff
    private static final String INCOMINGDIR = "xfer";
    private File incomingdir = null;
    
    /**
     *  Create a new xfer daemon for the specified user name.
     **/
    public XferDaemon( OutputPipe console, PeerGroup group, String userName, PipeAdvertisement adv ) {
        super( "Shell Xfer Daemon : " + userName );
        setDaemon( true );
        
        this.console = console;
        this.group = group;
        this.userName = userName;
        this.adv = adv;
        
        try {
            setupIncomingDir();
        } catch( IOException failed ) {
            printStackTrace( "Failed creating directory for receiving files.", failed );
            throw new UndeclaredThrowableException( failed );
        }
        
        if( null != adv ) {
            try {
                pipeIn = group.getPipeService().createInputPipe( adv, this );
            } catch ( IOException failure ) {
                printStackTrace( "Xfer daemon for '" + userName + "' caught exception opening input pipe.", failure );
            }
            
            if (pipeIn == null) {
                consoleMessage( "Failed to construct Input Pipe for : " + adv.getPipeID() );
                
                throw new RuntimeException( "Could not open Input Pipe to :" + adv.getPipeID() );
            }
            
            consoleMessage( "Logged in user '" + userName + "' as " + pipeIn.getType() + " Input Pipe Listener." );
            
            // republish the advertisement as our own.
            try {
                DiscoveryService disco = group.getDiscoveryService();
                
                disco.publish( adv, DiscoveryService.DEFAULT_LIFETIME, DiscoveryService.DEFAULT_EXPIRATION );
            } catch ( IOException failure ) {
                printStackTrace( "Xfer daemon for '" + userName + "' caught exception publishing pipe advertisement.", failure );
            }
        } else {
            try {
                EndpointService endpoint = group.getEndpointService();
                endpointListenerRegistered = endpoint.addIncomingMessageListener( this, XFERSERVICENAME, userName );
            } catch ( Throwable failure ) {
                printStackTrace( "Xfer daemon for '" + userName + "' caught exception registering Endpoint Listener.", failure );
            }
            
            if( !endpointListenerRegistered ) {
                consoleMessage( "Failed to register endpoint listener for : " + adv.getPipeID() );
                
                throw new RuntimeException( "Could not login endpoint listener for: " + XFERSERVICENAME + "/" + userName );
            }
            
            consoleMessage( "Logged in user '" + userName + "' as Endpoint Listener." );
        }
        start();
    }
    
    /**
     *  {@inheritDoc}
     **/
    public void run() {
        
        try {
            while( !closed ) {
                try {
                    synchronized( this ) {
                        wait();
                    }
                } catch ( InterruptedException woken ) {
                    Thread.interrupted();
                }
            }
            
            consoleMessage( "Xfer daemon for '" + userName + "' closing." );
        } catch ( Throwable all ) {
            printStackTrace( "Xfer daemon for '" + userName + "' caught exception!", all );
        } finally {
            closed = true;
        }
    }
    
    /**
     *  Close this daemon.
     **/
    synchronized void close() {
        
        if( null != pipeIn ) {
            pipeIn.close();
            pipeIn = null;
        }
        
        if( endpointListenerRegistered ) {
            EndpointService endpoint = group.getEndpointService();
            endpoint.removeIncomingMessageListener( XFERSERVICENAME, userName );
            endpointListenerRegistered = false;
        }
        
        closed = true;
        notifyAll();
    }
    
    
    /**
     *  Return the pipe advertisment associated with this daemon if any.
     *
     *  @return pipe advertisemnt for this daemon. will be null if daemon is
     *  registered as an endpoint listener rather than a pipe listener
     **/
    PipeAdvertisement getPipeAdvertisment( ) {
        return adv;
    }
    
    /**
     *  Return the pipe advertisment associated with this daemon if any.
     *
     *  @return User name associated with this daemon.
     **/
    String getUserName( ) {
        return userName;
    }
    
    /**
     *  Create the received file directory.
     **/
    private void setupIncomingDir() throws IOException {
        String userhome = null;
        
        try {
            userhome = System.getProperty("user.home");
        } catch (Exception ignored) {;}	// should never happen
        
        incomingdir = new File( userhome + File.separator + INCOMINGDIR );
        
        if (!incomingdir.exists()) {
            if (!incomingdir.mkdirs()) {
                throw new IOException( "Could not create : " + incomingdir );
            }
        }
    }
    
    // Private implementations
    
    private void print( String line ) {
        ShellApp.pipePrint( console, line );
    }
    
    private void println( String line ) {
        print( line + "\n" );
    }
    
    private void consoleMessage( String message ) {
        ShellApp.consoleMessage( this.getClass(), console, message );
    }
    
    private void printStackTrace( String annotation, Throwable failure ) {
        ShellApp.printStackTrace( this.getClass(), console, annotation, failure );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public void pipeMsgEvent(PipeMsgEvent event) {
        Message msg = event.getMessage();
        
        processIncomingMessage( msg, null, null );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public void processIncomingMessage( Message message, EndpointAddress srcAddr, EndpointAddress dstAddr ) {
        
        try {
            // This is a message part of a file transfer.
            MessageElement newXfer = message.getMessageElement( xfer.XFERFILEINFO_ELEMENT );
            
            MessageElement oldXfer = message.getMessageElement( xfer.XFERIDENTIFIER_ELEMENT );
            
            if( null == oldXfer ) {
                consoleMessage( "No file identifier"  );
                return;
            }
            
            String identifier = oldXfer.toString();
            FileReceiver thisFile;
            
            if( null != newXfer ) {
                synchronized (incoming) {
                    thisFile = new FileReceiver( group, console, incomingdir, newXfer );
                    
                    incoming.put( identifier, thisFile );
                }
            } else {
                thisFile = (FileReceiver) incoming.get( identifier );
            }
            
            if( null != thisFile ) {
                MessageElement sequenceElement = message.getMessageElement( xfer.XFERSEQUENCE_ELEMENT );
                
                int sequence = Integer.parseInt(sequenceElement.toString());
                
                MessageElement dataElement = message.getMessageElement( xfer.XFERDATA_ELEMENT );
                
                boolean done = thisFile.processElement( sequence, dataElement );
                
                if( done ) {
                    synchronized (incoming) {
                        incoming.remove( identifier );
                    }
                }
            } else {
                consoleMessage( "No handler for : " + identifier );
            }
        } catch( Throwable all ) {
            printStackTrace( "Xfer daemon for '" + userName + "' caught exception!", all );
        }
    }
}