filereceiver.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: FileReceiver.java,v 1.8 2004/09/29 20:44:43 bondolo Exp $
 */


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

import java.io.DataInputStream;
import java.io.File;
import java.io.PrintWriter;
import java.io.RandomAccessFile;
import java.io.StringReader;
import java.io.StringWriter;
import java.net.URI;

import java.io.IOException;
import java.net.URISyntaxException;

import net.jxta.discovery.DiscoveryService;
import net.jxta.document.Advertisement;
import net.jxta.document.AdvertisementFactory;
import net.jxta.document.MimeMediaType;
import net.jxta.endpoint.MessageElement;
import net.jxta.id.IDFactory;
import net.jxta.peer.PeerID;
import net.jxta.peergroup.PeerGroup;
import net.jxta.protocol.PipeAdvertisement;
import net.jxta.pipe.OutputPipe;

import net.jxta.impl.shell.ShellApp;

/**
 *  Manages a file being received.
 **/
class FileReceiver {
    RandomAccessFile fout;
    OutputPipe console;
    
    String srcUserName;
    String srcPipeAdv;
    String identifier;
    String filename;
    File file;
    long filesize;
    long blockSize;
    int chunks;
    boolean [] receivedChunks;
    
    long written;
    long starttime;
    
    FileReceiver( PeerGroup group, OutputPipe console, File incomingdir, MessageElement newXfer ) throws IOException {
        this.console = console;
        
        DataInputStream dis = new DataInputStream( newXfer.getStream() );
        
        int fileinfoversion = dis.readInt();
        
        if( fileinfoversion != xfer.XFERFILEINFO_VERSION ) {
            throw new IllegalArgumentException( "Incorrect file info version" );
        }
        
        PeerID srcPeerID = null;
        
        try {
            URI peerID =  new URI( dis.readUTF() );
            srcPeerID = (PeerID) IDFactory.fromURI( peerID );
        } catch ( URISyntaxException badID ) {
            throw new IllegalArgumentException( "Bad peer ID in header");
        } catch ( ClassCastException badID ) {
            throw new IllegalArgumentException( "Non peer ID in header");
        }
        
        srcUserName = dis.readUTF();
        srcPipeAdv = dis.readUTF();
        long srcPipeExp = dis.readLong();
        identifier = dis.readUTF();
        filename = dis.readUTF();
        filesize = dis.readLong();
        blockSize = dis.readLong();
        
        consoleMessage( "New Incoming " + identifier + " file '" + filename + "' ("+ filesize +") from '" + srcUserName + "'." );
        
        // Save the pipe Adv of the endpoint
        if( srcPipeAdv.length() > 0 ) {
            try {
                Advertisement srcPipe = AdvertisementFactory.newAdvertisement( MimeMediaType.XMLUTF8, new StringReader( srcPipeAdv ) );
                
                if( srcPipe instanceof PipeAdvertisement ) {
                    DiscoveryService disco = group.getDiscoveryService();
                    
                    consoleMessage( "Publishing sender pipe advertisment for user '" +  srcUserName + "' with expiry of " + srcPipeExp + " millis." );
                    disco.publish(srcPipe, srcPipeExp, srcPipeExp );
                }
            }  catch( Throwable all ) {
                printStackTrace( "Failed to publish pipe advertisment for user '" +  srcUserName + "'.", all );
            }
        }
        
        written = 0;
        chunks = (int) (filesize / blockSize) + ((0 != (filesize % blockSize)) ? 1 : 0);
        receivedChunks = new boolean[(int)chunks];
        
        file = new File( incomingdir, filename );
        
        if (file.exists()) {
            // We should not overwrite an existing file. Instead, create a new file.
            file = new File(incomingdir, filename + ".copy");
            if (file.exists()) {
                file.delete();
            }
        }
        
        file.createNewFile();
        fout = new RandomAccessFile( file, "rw" );
        fout.setLength( filesize );
        
        starttime = System.currentTimeMillis();
    }
    
    // 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 );
    }
    
    /**
     *  processes a chunk of a file.
     *
     *  @param chunk    the index number of the chunk.
     *  @param element  the element containing the data for the chunk.
     *  @return true if the file transfer is complete, otherwise false.
     **/
    synchronized boolean  processElement( int chunk, MessageElement element ) throws IOException {
        if( null == fout ) {
            return true;
        }
        
        fout.seek( chunk * blockSize );
        
        fout.write( element.getBytes( false ) );
        
        written += element.getByteLength();
        
        print( "!" );
        
        receivedChunks[chunk] = true;
        
        if( filesize <= written ) {
            fout.getFD().sync();
            fout.close();
            fout = null;
            
            println(" Done");
            
            // elapsed time and bytes per sec.
            long elapsedTime = System.currentTimeMillis() - starttime;
            
            // div by 0 check
            if (elapsedTime == 0) {
                elapsedTime = 1;
            }
            
            long kbpsec = (long)(((long)filesize)/elapsedTime);
            float secs = (float)(((float)elapsedTime)/1000.0);
            
            consoleMessage( "Received '" + filename + "' (" + filesize + ") in "  + secs + " secs[" + kbpsec + "KBytes/sec]");
            
            return true;
        }
        
        return false;
    }
}