outgoingpipeadaptorsync.java

jxta平台的开发包

/*
 *
 * Copyright (c) 2003-2006 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.util.pipe.reliable;

import java.io.IOException;
import java.lang.IllegalStateException;
import java.util.List;
import java.util.ArrayList;

import org.apache.log4j.Level;
import org.apache.log4j.Logger;

import net.jxta.pipe.OutputPipe;
import net.jxta.endpoint.Message;
import net.jxta.impl.util.TimeUtils;

public class OutgoingPipeAdaptorSync implements Outgoing {

    private static final Logger LOG = 
        Logger.getLogger(OutgoingPipeAdaptor.class.getName());

    private OutputPipe pipe = null;
    private long lastAccessed = 0;
    private boolean closed = false;

    public OutgoingPipeAdaptorSync(OutputPipe pipe) {

        // Null permitted. Send will block until setPipe is called.
        this.pipe = pipe;

        // initialize to some reasonable value
        lastAccessed = TimeUtils.timeNow();
    }

    public boolean sendNb(Message msg) throws IOException {
        OutputPipe locPipe = null;

        synchronized (this) {
            locPipe = pipe;
        }

        if (closed || locPipe == null) return false;

        locPipe.send(msg);

        return true;
    }

    public boolean send(Message msg) throws IOException {

        OutputPipe locPipe = null;

        synchronized (this) {
            while (pipe == null && !closed) {
                try {
                    wait();
                } catch (InterruptedException ignore) {
                }
            }
            if (closed) return false;
            locPipe = pipe;
        }

        locPipe.send(msg);

        return true;
    }

    public void setPipe(OutputPipe pipe) {
        synchronized(this) {
            if (closed || this.pipe != null) {
                throw new IllegalStateException("Cannot change pipe nor re-open");
            }
            this.pipe = pipe;
            notifyAll();
        }
    }

    /**
     *  {@inheritDoc}
     */
    public void close() throws IOException {
        synchronized(this) {
            if (closed) return;
            closed = true;
        }
        if (pipe != null) {
            pipe.close();
            pipe = null;
        }
    }

    /**
     *  {@inheritDoc}
     */
    public long getMinIdleReconnectTime() {
        return 10 * TimeUtils.AMINUTE;
    }

    /**
     *  {@inheritDoc}
     *
     * <p/>Default should be "never", otherwise, connection closes while not
     * in active use and ReliableOutputStream does NOT reconnect automatically.
     */
    public long getIdleTimeout() {
        return Long.MAX_VALUE;
    }

    /**
     *  {@inheritDoc}
     *
     *  <p/>This is the important tunable: how long to wait on a stale connection.
     */
    public long getMaxRetryAge() {
        return 1 * TimeUtils.AMINUTE;
    }

    /**
     *  {@inheritDoc}
     */
    public long getLastAccessed() {
        return lastAccessed;
    }

    /**
     *  {@inheritDoc}
     */
    public void setLastAccessed(long time) {
        lastAccessed = time;
    }

    /**
     *  {@inheritDoc}
     */
    public String toString() {
        return ((pipe == null) ? "no pipe yet" : pipe.toString()) + 
            " lastAccessed=" + Long.toString(lastAccessed);
    }
}