org.jivesoftware.smackx.filetransfer.FaultTolerantNegotiator Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of smack Show documentation
Smack is an Open Source XMPP (Jabber) client library for instant messaging and presence. This library provides the client side functionality as specified in the core XMPP specifications as related to the client side of said specifications.
The newest version!
/**
 * $RCSfile$
 * $Revision: $
 * $Date: $
 *
 * Copyright 2003-2006 Jive Software.
 *
 * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.jivesoftware.smackx.filetransfer;

import org.jivesoftware.smack.PacketCollector;
import org.jivesoftware.smack.SmackConfiguration;
import org.jivesoftware.smack.Connection;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.filter.OrFilter;
import org.jivesoftware.smack.filter.PacketFilter;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smackx.packet.StreamInitiation;

import java.io.InputStream;
import java.io.OutputStream;
import java.util.concurrent.*;
import java.util.List;
import java.util.ArrayList;


/**
 * The fault tolerant negotiator takes two stream negotiators, the primary and the secondary
 * negotiator. If the primary negotiator fails during the stream negotiaton process, the second
 * negotiator is used.
 */
public class FaultTolerantNegotiator extends StreamNegotiator {

    private StreamNegotiator primaryNegotiator;
    private StreamNegotiator secondaryNegotiator;
    private Connection connection;
    private PacketFilter primaryFilter;
    private PacketFilter secondaryFilter;

    public FaultTolerantNegotiator(Connection connection, StreamNegotiator primary,
            StreamNegotiator secondary) {
        this.primaryNegotiator = primary;
        this.secondaryNegotiator = secondary;
        this.connection = connection;
    }

    public PacketFilter getInitiationPacketFilter(String from, String streamID) {
        if (primaryFilter == null || secondaryFilter == null) {
            primaryFilter = primaryNegotiator.getInitiationPacketFilter(from, streamID);
            secondaryFilter = secondaryNegotiator.getInitiationPacketFilter(from, streamID);
        }
        return new OrFilter(primaryFilter, secondaryFilter);
    }

    InputStream negotiateIncomingStream(Packet streamInitiation) throws XMPPException {
        throw new UnsupportedOperationException("Negotiation only handled by create incoming " +
                "stream method.");
    }

    final Packet initiateIncomingStream(Connection connection, StreamInitiation initiation) {
        throw new UnsupportedOperationException("Initiation handled by createIncomingStream " +
                "method");
    }

    public InputStream createIncomingStream(StreamInitiation initiation) throws XMPPException {
        PacketCollector collector = connection.createPacketCollector(
                getInitiationPacketFilter(initiation.getFrom(), initiation.getSessionID()));

        connection.sendPacket(super.createInitiationAccept(initiation, getNamespaces()));

        CompletionService service
                = new ExecutorCompletionService(Executors.newFixedThreadPool(2));
        List> futures = new ArrayList>();
        InputStream stream = null;
        XMPPException exception = null;
        try {
            futures.add(service.submit(new NegotiatorService(collector)));
            futures.add(service.submit(new NegotiatorService(collector)));

            int i = 0;
            while (stream == null && i < futures.size()) {
                Future future;
                try {
                    i++;
                    future = service.poll(10, TimeUnit.SECONDS);
                }
                catch (InterruptedException e) {
                    continue;
                }

                if (future == null) {
                    continue;
                }

                try {
                    stream = future.get();
                }
                catch (InterruptedException e) {
                    /* Do Nothing */
                }
                catch (ExecutionException e) {
                    exception = new XMPPException(e.getCause());
                }
            }
        }
        finally {
            for (Future future : futures) {
                future.cancel(true);
            }
            collector.cancel();
        }
        if (stream == null) {
            if (exception != null) {
                throw exception;
            }
            else {
                throw new XMPPException("File transfer negotiation failed.");
            }
        }

        return stream;
    }

    private StreamNegotiator determineNegotiator(Packet streamInitiation) {
        return primaryFilter.accept(streamInitiation) ? primaryNegotiator : secondaryNegotiator;
    }

    public OutputStream createOutgoingStream(String streamID, String initiator, String target)
            throws XMPPException {
        OutputStream stream;
        try {
            stream = primaryNegotiator.createOutgoingStream(streamID, initiator, target);
        }
        catch (XMPPException ex) {
            stream = secondaryNegotiator.createOutgoingStream(streamID, initiator, target);
        }

        return stream;
    }

    public String[] getNamespaces() {
        String[] primary = primaryNegotiator.getNamespaces();
        String[] secondary = secondaryNegotiator.getNamespaces();

        String[] namespaces = new String[primary.length + secondary.length];
        System.arraycopy(primary, 0, namespaces, 0, primary.length);
        System.arraycopy(secondary, 0, namespaces, primary.length, secondary.length);

        return namespaces;
    }

    public void cleanup() {
    }

    private class NegotiatorService implements Callable {

        private PacketCollector collector;

        NegotiatorService(PacketCollector collector) {
            this.collector = collector;
        }

        public InputStream call() throws Exception {
            Packet streamInitiation = collector.nextResult(
                    SmackConfiguration.getPacketReplyTimeout() * 2);
            if (streamInitiation == null) {
                throw new XMPPException("No response from remote client");
            }
            StreamNegotiator negotiator = determineNegotiator(streamInitiation);
            return negotiator.negotiateIncomingStream(streamInitiation);
        }
    }
}