shelloutputpipe.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: ShellOutputPipe.java,v 1.26 2006/06/14 16:37:12 bondolo Exp $
 */

package net.jxta.impl.shell;

import java.util.Iterator;

import java.util.logging.Logger;
import java.util.logging.Level;

import net.jxta.endpoint.Message;
import net.jxta.endpoint.MessageElement;
import net.jxta.peergroup.PeerGroup;
import net.jxta.pipe.OutputPipe;
import net.jxta.protocol.PipeAdvertisement;
import net.jxta.id.ID;

import net.jxta.impl.util.ConsumerBiasedQueue;
import net.jxta.impl.util.UnbiasedQueue;

/**
 * This class implements the default  JXTA Shell OutputPipe.
 * Message received on the pipe are displayed onto the console.
 */

public class ShellOutputPipe implements Runnable, OutputPipe {
    
    /**
     *  Log4J Logger
     */
    private static final transient java.util.logging.Logger LOG = java.util.logging.Logger.getLogger(ShellOutputPipe.class.getName());;
    
    private ShellConsole cons;
    
    private Thread thread;
    private UnbiasedQueue queue;
    
    public ShellOutputPipe( PeerGroup group, ShellConsole cons ) {
        
        this.cons = cons;
        queue = UnbiasedQueue.synchronizedQueue(new ConsumerBiasedQueue() );
        
        
        thread = new Thread( group.getHomeThreadGroup(), this, "ShellOutputPipe-" + cons.getConsoleName() );
        thread.setDaemon(true);
        thread.start();
    }
    
    /**
     *  {@inheritDoc}
     **/
    public boolean send( Message msg ) {
        return queue.push( msg );
    }
    
    /**
     *  {@inheritDoc}
     *
     *  <p/>Not implemented.
     **/
    public PipeAdvertisement getAdvertisement() {
        throw new UnsupportedOperationException( "Not supported by ShellOutputPipe" );
    }
    
    /**
     *  {@inheritDoc}
     *
     *  <p/>Not implemented.
     **/
    public String getName() {
        throw new UnsupportedOperationException( "Not supported by ShellOutputPipe" );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public ID getPipeID() {
        throw new UnsupportedOperationException( "Not supported by ShellOutputPipe" );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public String getType() {
        throw new UnsupportedOperationException( "Not supported by ShellOutputPipe" );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public synchronized void close() {
        queue.close();
        if (thread != null) {
            thread.interrupt();
        }
    }
    
    /**
     *  {@inheritDoc}
     **/
    public boolean isClosed() {
        return queue.isClosed();
    }
    
    /**
     *  {@inheritDoc}
     **/
    public void run() {
        
        try {
            while (true) {
                Message msg = null;

                try {
                    msg = (Message) queue.pop(0);
                }
                catch (InterruptedException woken) {
                    Thread.interrupted();
                    continue;
                }
                if (msg == null) {
                    if (queue.isClosed()) {
                        break;
                    }
                    else {
                        continue;
                    }
                }
                // Get all the chunks of data in the message
                Iterator els = msg.getMessageElementsOfNamespace(null);

                while (els.hasNext()) {
                    MessageElement el = (MessageElement) els.next();

                    cons.write(el.toString());
                }
            }
        }
        catch (Throwable all) {
            if (LOG.isLoggable(java.util.logging.Level.SEVERE)) {
                LOG.log(java.util.logging.Level.SEVERE,
                        "Uncaught Throwable in Thread : " +
                        Thread.currentThread().getName(), all);
            }
        }
        finally {
            thread = null;
        }
    }
}