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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
/** * A closeable view over a read and write side of a suspendable channel. * * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a> */
public class AssembledChannel implements CloseableChannel { private final SuspendableReadChannel readChannel; private final SuspendableWriteChannel writeChannel; // Actual type is SimpleSetter<THIS> private final ChannelListener.SimpleSetter<AssembledChannel> closeSetter = new ChannelListener.SimpleSetter<AssembledChannel>(); private final ChannelListener<CloseableChannel> listener = new ChannelListener<CloseableChannel>() { 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<AssembledChannel> stateUpdater = AtomicIntegerFieldUpdater.newUpdater(AssembledChannel.class, "state");
Construct a new instance.
Params:
  • readChannel – the read side
  • writeChannel – the write side
/** * 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<? extends CloseableChannel> 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> T nonNullOrFirst(T one, T two) { return one != null ? one : two; } public <T> T getOption(final Option<T> option) throws IOException { return nonNullOrFirst(readChannel.getOption(option), writeChannel.getOption(option)); } public <T> T setOption(final Option<T> option, final T value) throws IllegalArgumentException, IOException { return nonNullOrFirst(readChannel.setOption(option, value), writeChannel.setOption(option, value)); } }