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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 2008 Red Hat, Inc. and/or its affiliates.
 *
 * 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.streams;

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

import java.io.OutputStream;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.nio.ByteBuffer;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import org.xnio.Bits;
import org.xnio.channels.StreamSinkChannel;

/**
 * An output stream which writes to a stream sink channel.  All write operations are directly
 * performed upon the channel, so for optimal performance, a buffering output stream should be
 * used to wrap this class.
 *
 * @apiviz.exclude
 * 
 * @since 1.2
 */
public class ChannelOutputStream extends OutputStream {

    protected final StreamSinkChannel channel;
    @SuppressWarnings("unused")
    private volatile int flags;
    private volatile long timeout;

    private static final AtomicIntegerFieldUpdater flagsUpdater = AtomicIntegerFieldUpdater.newUpdater(ChannelOutputStream.class, "flags");

    private static final int FLAG_CLOSED = 2;
    private static final int FLAG_ENTERED = 1;

    /**
     * Construct a new instance.  No write timeout is configured.
     *
     * @param channel the channel to wrap
     */
    public ChannelOutputStream(final StreamSinkChannel channel) {
        if (channel == null) {
            throw msg.nullParameter("channel");
        }
        this.channel = channel;
    }

    /**
     * Construct a new instance.
     *
     * @param channel the channel to wrap
     * @param timeout the write timeout
     * @param unit the write timeout units
     */
    public ChannelOutputStream(final StreamSinkChannel channel, final long timeout, final TimeUnit unit) {
        if (channel == null) {
            throw msg.nullParameter("channel");
        }
        if (unit == null) {
            throw msg.nullParameter("unit");
        }
        if (timeout < 0L) {
            throw msg.parameterOutOfRange("timeout");
        }
        this.channel = channel;
        final long calcTimeout = unit.toNanos(timeout);
        this.timeout = timeout == 0L ? 0L : calcTimeout < 1L ? 1L : calcTimeout;
    }

    private boolean enter() {
        int old = flags;
        do {
            if (Bits.allAreSet(old, FLAG_ENTERED)) {
                throw msg.concurrentAccess();
            }
        } while (! flagsUpdater.compareAndSet(this, old, old | FLAG_ENTERED));
        return Bits.allAreSet(old, FLAG_CLOSED);
    }

    private void exit(boolean setEof) {
        int oldFlags, newFlags;
        do {
            oldFlags = flags;
            newFlags = oldFlags &~ FLAG_ENTERED;
            if (setEof) {
                newFlags |= FLAG_CLOSED;
            }
        } while (! flagsUpdater.compareAndSet(this, oldFlags, newFlags));
    }

    /**
     * Get the write timeout.
     *
     * @param unit the time unit
     * @return the timeout in the given unit
     */
    public long getWriteTimeout(TimeUnit unit) {
        if (unit == null) {
            throw msg.nullParameter("unit");
        }
        return unit.convert(timeout, TimeUnit.NANOSECONDS);
    }

    /**
     * Set the write timeout.  Does not affect write operations in progress.
     *
     * @param timeout the write timeout, or 0 for none
     * @param unit the time unit
     */
    public void setWriteTimeout(long timeout, TimeUnit unit) {
        if (timeout < 0L) {
            throw msg.parameterOutOfRange("timeout");
        }
        if (unit == null) {
            throw msg.nullParameter("unit");
        }
        final long calcTimeout = unit.toNanos(timeout);
        this.timeout = timeout == 0L ? 0L : calcTimeout < 1L ? 1L : calcTimeout;
    }

    /** {@inheritDoc} */
    public void write(final int b) throws IOException {
        boolean closed = enter();
        try {
            if (closed) throw msg.streamClosed();
            final StreamSinkChannel channel = this.channel;
            final ByteBuffer buffer = ByteBuffer.wrap(new byte[] { (byte) b });
            int res = channel.write(buffer);
            if (res == 0) {
                long timeout;
                long start = System.nanoTime();
                long elapsed = 0L;
                do {
                    timeout = this.timeout;
                    if (timeout == 0L) {
                        channel.awaitWritable();
                    } else if (timeout < elapsed) {
                        throw msg.writeTimeout();
                    } else {
                        channel.awaitWritable(timeout - elapsed, TimeUnit.NANOSECONDS);
                    }
                    elapsed = System.nanoTime() - start;
                    res = channel.write(buffer);
                } while (res == 0);
            }
        } finally {
            exit(closed);
        }
    }

    /** {@inheritDoc} */
    public void write(final byte[] b) throws IOException {
        write(b, 0, b.length);
    }

    /** {@inheritDoc} */
    public void write(final byte[] b, final int off, final int len) throws IOException {
        if (len < 1) {
            return;
        }
        boolean closed = enter();
        try {
            if (closed) throw msg.streamClosed();
            final StreamSinkChannel channel = this.channel;
            final ByteBuffer buffer = ByteBuffer.wrap(b, off, len);
            int res;
            while (buffer.hasRemaining()) {
                res = channel.write(buffer);
                if (res == 0) {
                    long timeout;
                    long start = System.nanoTime();
                    long elapsed = 0L;
                    do {
                        timeout = this.timeout;
                        try {
                            if (timeout == 0L) {
                                channel.awaitWritable();
                            } else if (timeout < elapsed) {
                                throw msg.writeTimeout();
                            } else {
                                channel.awaitWritable(timeout - elapsed, TimeUnit.NANOSECONDS);
                            }
                        } catch (InterruptedIOException e) {
                            e.bytesTransferred = buffer.position() - off;
                            throw e;
                        }
                        elapsed = System.nanoTime() - start;
                        res = channel.write(buffer);
                    } while (res == 0);
                }
            }
        } finally {
            exit(closed);
        }
    }

    /** {@inheritDoc} */
    public void flush() throws IOException {
        final boolean closed = enter();
        try {
            final StreamSinkChannel channel = this.channel;
            if (! channel.flush()) {
                long timeout;
                long start = System.nanoTime();
                long elapsed = 0L;
                do {
                    timeout = this.timeout;
                    if (timeout == 0L) {
                        channel.awaitWritable();
                    } else if (timeout < elapsed) {
                        throw msg.writeTimeout();
                    } else {
                        channel.awaitWritable(timeout - elapsed, TimeUnit.NANOSECONDS);
                    }
                    elapsed = System.nanoTime() - start;
                } while (! channel.flush());
            }
        } finally {
            exit(closed);
        }
    }

    /** {@inheritDoc} */
    public void close() throws IOException {
        final boolean closed = enter();
        try {
            if (closed) return;
            final StreamSinkChannel channel = this.channel;
            channel.shutdownWrites();
            if (! channel.flush()) {
                long timeout;
                long start = System.nanoTime();
                long elapsed = 0L;
                do {
                    timeout = this.timeout;
                    if (timeout == 0L) {
                        channel.awaitWritable();
                    } else if (timeout < elapsed) {
                        throw msg.writeTimeout();
                    } else {
                        channel.awaitWritable(timeout - elapsed, TimeUnit.NANOSECONDS);
                    }
                    elapsed = System.nanoTime() - start;
                } while (! channel.flush());
            }
        } finally {
            exit(true);
        }
    }
}




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