ch.cyberduck.core.http.DelayedHttpEntity.java Source code

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Here is the source code for ch.cyberduck.core.http.DelayedHttpEntity.java

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package ch.cyberduck.core.http;

/*
 * Copyright (c) 2002-2011 David Kocher. All rights reserved.
 *
 * http://cyberduck.ch/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Bug fixes, suggestions and comments should be sent to:
 * dkocher@cyberduck.ch
 */

import org.apache.commons.io.output.NullOutputStream;
import org.apache.http.entity.AbstractHttpEntity;
import org.apache.log4j.Logger;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.concurrent.CountDownLatch;

public abstract class DelayedHttpEntity extends AbstractHttpEntity {
    private static final Logger log = Logger.getLogger(DelayedHttpEntity.class);

    private final CountDownLatch entry;
    private final CountDownLatch exit = new CountDownLatch(1);

    public DelayedHttpEntity() {
        this(new CountDownLatch(1));
    }

    /**
     * @param entry Signal when stream is ready
     */
    public DelayedHttpEntity(final CountDownLatch entry) {
        this.entry = entry;
    }

    /**
     * HTTP stream to write to
     */
    private OutputStream stream;
    /**
     *
     */
    private boolean consumed = false;

    public boolean isRepeatable() {
        return true;
    }

    public abstract long getContentLength();

    public InputStream getContent() throws IOException {
        throw new IOException(new UnsupportedOperationException("No content here"));
    }

    /**
     * @return The stream to write to after the entry signal was received.
     */
    public OutputStream getStream() {
        if (null == stream) {
            // Nothing to write
            return NullOutputStream.NULL_OUTPUT_STREAM;
        }
        return stream;
    }

    public void writeTo(final OutputStream out) throws IOException {
        try {
            stream = new OutputStream() {
                @Override
                public void write(final byte[] b, final int off, final int len) throws IOException {
                    out.write(b, off, len);
                }

                @Override
                public void write(final int b) throws IOException {
                    out.write(b);
                }

                @Override
                public void write(final byte[] b) throws IOException {
                    out.write(b);
                }

                @Override
                public void close() throws IOException {
                    try {
                        super.close();
                    } finally {
                        // Signal finished writing to stream
                        exit.countDown();
                    }
                }
            };
        } finally {
            entry.countDown();
        }
        // Wait for signal when content has been written to the pipe
        try {
            exit.await();
        } catch (InterruptedException e) {
            log.error(String.format("Error waiting for exit signal %s", e.getMessage()));
            throw new IOException(e);
        }
        // Entity written to server
        consumed = true;
    }

    public boolean isStreaming() {
        return !consumed;
    }

    /**
     * @return Set when output stream is ready
     */
    public CountDownLatch getEntry() {
        return entry;
    }
}