nonblockingoutputpipe.java

jxme的一些相关程序,主要是手机上程序开发以及手机和计算机通信的一些程序资料,程序编译需要Ant支持

/*
 *
 * $Id: NonBlockingOutputPipe.java,v 1.2 2002/03/04 21:42:59 echtcherbina Exp $
 *
 * 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.
 */

package net.jxta.impl.pipe;

import java.io.*;
import java.util.*;
import org.apache.log4j.Category; import org.apache.log4j.Priority;

import net.jxta.endpoint.*;
import net.jxta.peergroup.*;
import net.jxta.pipe.*;
import net.jxta.peer.PeerID;
import net.jxta.id.*;
import net.jxta.protocol.*;

import java.net.URL;

/**
 * This class implements the non blocking Output PipeServiceImpl.
 *
 */


public class NonBlockingOutputPipe implements OutputPipe {
    private static final Category LOG = Category.getInstance(NonBlockingOutputPipe.class.getName());

    private String pipeId = null;
    private PeerGroup myGroup = null;
    private EndpointService endpoint = null;
    private PipeResolver myPipeResolver = null;
    private EndpointAddress destAddress = null;
    private EndpointMessenger destMessenger = null;
    private String peer = null;
    private static final long RetryDelay = 5000; // 5 seconds
    private boolean closed = false;
    private PipeAdvertisement pAdv = null;

    private EndpointAddress mkAddress(String destPeer, String pipeId) {
        try {
            PeerID asID = (PeerID) IDFactory.fromURL(new URL(destPeer));
            String asString = "jxta://" + asID.getUniqueValue().toString();

            EndpointAddress addr = endpoint.newEndpointAddress(asString);
            addr.setServiceName("PipeService");
            addr.setServiceParameter(pipeId);
            return addr;
        } catch (Exception e) {
            if (LOG.isEnabledFor(Priority.ERROR)) LOG.error("invalid PeerID string: " + destPeer);
            return null;
        }
    }
    
    public NonBlockingOutputPipe (PeerGroup g,
                                  PipeResolver r,
                                  PipeAdvertisement pAdv,
                                  String destPeer,
                                  long timeout)
                     throws IOException {

        myGroup = g;
        endpoint = g.getEndpointService();

	this.pAdv = pAdv;
	ID opId = pAdv.getPipeID();
        pipeId = opId.toString();
        myPipeResolver = r;

        if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Constructor for " + opId);
        // Search for the pipe

        peer = null;
        if (destPeer == null) {
            peer = myPipeResolver.find (pAdv, timeout, false);

            if (peer == null) {
                // PipeResolver was not able to find that pipe.
                if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Constructor: no matching InputPipe for " + opId);
                throw new IOException("Constructor: no matching InputPipe for " + opId);
            }
        } else {
            peer = destPeer;
        }

        // Send an asynchronous handcheck to the peer that is
        // supposed to have the pipe.
        myPipeResolver.sendVerify (peer, pipeId, PipeService.UnicastType);

        // Get an endpoint messenger to that address
        destMessenger = endpoint.getMessenger (mkAddress(peer, pipeId));
        
        if (destMessenger == null) {
            if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Constructor: no EndpointService Messenger for " + opId);
            throw new IOException ("Constructor: no EndpointService Messenger for " + opId);
        }
    }
    
    /**
     *  create an outputpipe object without resolving it to a peer,
     *  this is soley used by pipe resolver listeners
     */

    protected NonBlockingOutputPipe (PeerGroup g,
				     PipeResolver r,
				     PipeAdvertisement pAdv,
				     String destPeer)
                     throws IOException {
                         
        myGroup = g;
	this.pAdv =pAdv;
        endpoint = g.getEndpointService();
	ID opId = pAdv.getPipeID();
        pipeId = opId.toString();
        peer = destPeer;
        myPipeResolver = r;

        if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Constructor for " + opId);

        // Get an endpoint messenger to that address
        destMessenger = endpoint.getMessenger (mkAddress(destPeer, pipeId));
        if (destMessenger == null) {
            if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Constructor: no EndpointService Messenger for " + opId);
            throw new IOException ("Constructor: no EndpointService Messenger for " + opId);
        }
    }    
    /**
     * send a message
     *
     * @param msg is the PipeMessage to be sent.
     */

    public void send (Message msg) throws IOException {
        if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("send");
        String cachedPeer = myPipeResolver.findLocal (pipeId);
        if (cachedPeer == null) {
            // The InputPipe is not where it is supposed to be.
            // Find it, and throw an exception.
            cachedPeer = myPipeResolver.find (pAdv, RetryDelay, true);
            if (peer == null) {
                throw new IOException("null dest peer");
            }
        }
        if ( ! cachedPeer.equals (peer) ) {
            // The pipe has moved. Get a new EndpointService
            peer = cachedPeer;
            destMessenger.close();
            destMessenger = endpoint.getMessenger (mkAddress(peer, pipeId));

            if (destMessenger == null) {
                if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("sendMessage: no EndpointService Messenger for " +pipeId);
                throw new IOException ("sendMessage: no EndpointService Messenger for " +pipeId);
            }
        }
        destMessenger.sendMessage (msg);
    }

    /**
     * close the the pipe
     *
     */
    public synchronized void close() {
        // Close the messenger.
        destMessenger.close();
        closed = true;

    }

    protected void finalize() throws Throwable {
        if (!closed) {
            close();
        }
    }
}