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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 *
 * Copyright 2012 Red Hat, Inc. and/or its affiliates, and individual
 * contributors as indicated by the @author tags.
 *
 * 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.xnio.channels;

import java.io.IOException;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import org.xnio.ChannelListener;
import org.xnio.ChannelListeners;
import org.xnio.IoUtils;
import org.xnio.Option;
import org.xnio.XnioIoThread;
import org.xnio.XnioWorker;

import static org.xnio._private.Messages.msg;

/**
 * A closeable view over a read and write side of a suspendable channel.
 *
 * @author David M. Lloyd
 */
public class AssembledChannel implements CloseableChannel {

    private final SuspendableReadChannel readChannel;
    private final SuspendableWriteChannel writeChannel;

    // Actual type is SimpleSetter
    private final ChannelListener.SimpleSetter closeSetter = new ChannelListener.SimpleSetter();

    private final ChannelListener listener = new ChannelListener() {
        public void handleEvent(final CloseableChannel channel) {
            int newState, oldState;
            final AssembledChannel obj = AssembledChannel.this;
            do {
                oldState = stateUpdater.get(obj);
                if (oldState == 3) {
                    return;
                }
                newState = oldState;
                if (channel == readChannel) {
                    newState |= 1;
                }
                if (channel == writeChannel) {
                    newState |= 2;
                }
            } while (! stateUpdater.compareAndSet(obj, oldState, newState));
            if (newState == 3) {
                ChannelListeners.invokeChannelListener(obj, closeSetter.get());
            }
        }
    };

    @SuppressWarnings("unused")
    private volatile int state = 0;

    private static final AtomicIntegerFieldUpdater stateUpdater = AtomicIntegerFieldUpdater.newUpdater(AssembledChannel.class, "state");

    /**
     * Construct a new instance.
     *
     * @param readChannel the read side
     * @param writeChannel the write side
     */
    public AssembledChannel(final SuspendableReadChannel readChannel, final SuspendableWriteChannel writeChannel) {
        this.readChannel = readChannel;
        this.writeChannel = writeChannel;
        if (readChannel.getWorker() != writeChannel.getWorker()) {
            throw msg.differentWorkers();
        }
    }

    public ChannelListener.Setter getCloseSetter() {
        readChannel.getCloseSetter().set(listener);
        writeChannel.getCloseSetter().set(listener);
        return closeSetter;
    }

    public XnioWorker getWorker() {
        // both should be the same
        return readChannel.getWorker();
    }

    public XnioIoThread getIoThread() {
        // both should be the same
        return readChannel.getIoThread();
    }

    public void close() throws IOException {
        try {
            readChannel.close();
            writeChannel.close();
        } finally {
            IoUtils.safeClose(readChannel);
            IoUtils.safeClose(writeChannel);
        }
    }

    public boolean isOpen() {
        return readChannel.isOpen() && writeChannel.isOpen();
    }

    public boolean supportsOption(final Option option) {
        return readChannel.supportsOption(option) || writeChannel.supportsOption(option);
    }

    private static  T nonNullOrFirst(T one, T two) {
        return one != null ? one : two;
    }

    public  T getOption(final Option option) throws IOException {
        return nonNullOrFirst(readChannel.getOption(option), writeChannel.getOption(option));
    }

    public  T setOption(final Option option, final T value) throws IllegalArgumentException, IOException {
        return nonNullOrFirst(readChannel.setOption(option, value), writeChannel.setOption(option, value));
    }
}