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 * Copyright 2012 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.xnio.channels;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import org.xnio.ChannelListener;
import org.xnio.Option;
import org.xnio.XnioExecutor;
import org.xnio.XnioIoThread;
import org.xnio.XnioWorker;

import static org.xnio.Bits.*;
import static org.xnio.ChannelListeners.invokeChannelListener;

A half-duplex (write side) wrapper for a full-duplex channel.
Author:David M. Lloyd
/** * A half-duplex (write side) wrapper for a full-duplex channel. * * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a> */
public final class SplitStreamSinkChannel implements StreamSinkChannel, WriteListenerSettable<SplitStreamSinkChannel>, CloseListenerSettable<SplitStreamSinkChannel> { private final StreamSinkChannel delegate; private volatile int state; private ChannelListener<? super SplitStreamSinkChannel> writeListener; private ChannelListener<? super SplitStreamSinkChannel> closeListener; private static final int FLAG_DELEGATE_CONFIG = 1 << 0; private static final int FLAG_CLOSE_REQ = 1 << 1; private static final int FLAG_CLOSE_COMP = 1 << 2; private static final AtomicIntegerFieldUpdater<SplitStreamSinkChannel> stateUpdater = AtomicIntegerFieldUpdater.newUpdater(SplitStreamSinkChannel.class, "state");
Construct a new instance.
Params:
  • delegate – the delegate channel
  • delegateConfig – true to delegate configuration, false otherwise
/** * Construct a new instance. * * @param delegate the delegate channel * @param delegateConfig {@code true} to delegate configuration, {@code false} otherwise */
public SplitStreamSinkChannel(final StreamSinkChannel delegate, boolean delegateConfig) { this.delegate = delegate; state = delegateConfig ? FLAG_DELEGATE_CONFIG : 0; delegate.getWriteSetter().set(new ChannelListener<StreamSinkChannel>() { public void handleEvent(final StreamSinkChannel channel) { invokeChannelListener(SplitStreamSinkChannel.this, writeListener); } }); }
Construct a new instance which does not delegate configuration.
Params:
  • delegate – the delegate channel
/** * Construct a new instance which does not delegate configuration. * * @param delegate the delegate channel */
public SplitStreamSinkChannel(final StreamSinkChannel delegate) { this(delegate, false); } public void setWriteListener(final ChannelListener<? super SplitStreamSinkChannel> writeListener) { this.writeListener = writeListener; } public ChannelListener<? super SplitStreamSinkChannel> getWriteListener() { return writeListener; } public void setCloseListener(final ChannelListener<? super SplitStreamSinkChannel> closeListener) { this.closeListener = closeListener; } public ChannelListener<? super SplitStreamSinkChannel> getCloseListener() { return closeListener; } public ChannelListener.Setter<? extends SplitStreamSinkChannel> getCloseSetter() { return new CloseListenerSettable.Setter<SplitStreamSinkChannel>(this); } @Override public int writeFinal(ByteBuffer src) throws IOException { return delegate.writeFinal(src); } @Override public long writeFinal(ByteBuffer[] srcs, int offset, int length) throws IOException { return delegate.writeFinal(srcs, offset, length); } @Override public long writeFinal(ByteBuffer[] srcs) throws IOException { return delegate.writeFinal(srcs); } public ChannelListener.Setter<? extends SplitStreamSinkChannel> getWriteSetter() { return new WriteListenerSettable.Setter<SplitStreamSinkChannel>(this); } public void shutdownWrites() throws IOException { int oldVal, newVal; do { oldVal = state; if (allAreSet(oldVal, FLAG_CLOSE_REQ)) { return; } newVal = oldVal | FLAG_CLOSE_REQ; } while (! stateUpdater.compareAndSet(this, oldVal, newVal)); delegate.shutdownWrites(); } public boolean isOpen() { return allAreClear(state, FLAG_CLOSE_REQ); } public void close() throws IOException { shutdownWrites(); // best lame-duck effort; can't do any more than this really flush(); } public boolean flush() throws IOException { int oldVal, newVal; oldVal = state; if (allAreSet(oldVal, FLAG_CLOSE_COMP)) { return true; } final boolean flushed = delegate.flush(); if (! flushed) { return false; } do { if (allAreClear(oldVal, FLAG_CLOSE_REQ)) { return true; } newVal = oldVal | FLAG_CLOSE_COMP; } while (! stateUpdater.compareAndSet(this, oldVal, newVal)); invokeChannelListener(this, closeListener); return true; } public long transferFrom(final FileChannel src, final long position, final long count) throws IOException { return delegate.transferFrom(src, position, count); } public long transferFrom(final StreamSourceChannel source, final long count, final ByteBuffer throughBuffer) throws IOException { return delegate.transferFrom(source, count, throughBuffer); } public int write(final ByteBuffer src) throws IOException { return delegate.write(src); } public long write(final ByteBuffer[] srcs, final int offset, final int length) throws IOException { return delegate.write(srcs, offset, length); } public long write(final ByteBuffer[] srcs) throws IOException { return delegate.write(srcs); } public void suspendWrites() { delegate.suspendWrites(); } public void resumeWrites() { delegate.resumeWrites(); } public boolean isWriteResumed() { return delegate.isWriteResumed(); } public void wakeupWrites() { delegate.wakeupWrites(); } public void awaitWritable() throws IOException { delegate.awaitWritable(); } public void awaitWritable(final long time, final TimeUnit timeUnit) throws IOException { delegate.awaitWritable(time, timeUnit); } @Deprecated public XnioExecutor getWriteThread() { return delegate.getWriteThread(); } public XnioIoThread getIoThread() { return delegate.getIoThread(); } public XnioWorker getWorker() { return delegate.getWorker(); } public <T> T setOption(final Option<T> option, final T value) throws IllegalArgumentException, IOException { return allAreSet(state, FLAG_DELEGATE_CONFIG) ? delegate.setOption(option, value) : null; } public <T> T getOption(final Option<T> option) throws IOException { return allAreSet(state, FLAG_DELEGATE_CONFIG) ? delegate.getOption(option) : null; } public boolean supportsOption(final Option<?> option) { return allAreSet(state, FLAG_DELEGATE_CONFIG) ? delegate.supportsOption(option) : false; } }