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/*
 * $Header: /home/cvs/jakarta-commons/httpclient/src/test/org/apache/commons/httpclient/server/StreamProxy.java,v 1.1.2.1 2003/12/05 21:02:52 oglueck Exp $
 * $Revision: 1.1.2.1 $
 * $Date: 2003/12/05 21:02:52 $
 *
 * ====================================================================
 *
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * .
 *
 * [Additional notices, if required by prior licensing conditions]
 *
 */

package org.apache.commons.httpclient.server;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * Pipes all data of an input stream through to an output stream asynchronously.
 * Instances of this class are thread safe.
 * 
 * @author Ortwin Glueck
 */
class StreamProxy {
    private InputStream in;
    private OutputStream out;
    private Pump pump = new Pump();
    private Thread pumpThread = new Thread(pump, "Stream copier");
    private int state = 0;
  
    public StreamProxy(InputStream in, OutputStream out) {
        this.in = in;
        this.out = out;    
    }    
    
    public synchronized void start() {
        if (state != 0) throw new IllegalStateException("Can not start again.");
        state = 1;
        pumpThread.start();
    }
    
    /**
     * Returns immediately. The object must not be used again.
     */
    public void abort() {
        if (state != 1)  return;
        state = 2;
        pumpThread.interrupt();
        dispose();
    }
    
    /**
     * Blocks until all data has been copied. Basically calls the 
     * join method on the pump thread.
     * @throws InterruptedException
     */
    public void block() throws InterruptedException {
    	if (state != 1) throw new IllegalStateException("Can not block before started");
    	pumpThread.join();
    }
    
    private void dispose() {
        pumpThread = null;
        pump = null;
        in = null;
        out = null;
    }

    private class Pump implements Runnable {

        public void run() {
            byte[] buffer = new byte[10000];
            try {
                while (!Thread.interrupted()) {
                    int len;
                    while ((len = in.read(buffer)) != -1) {
                        out.write(buffer, 0, len);
                        out.flush();
                    }
                }
            } catch(IOException e) {
                /* expected if parties close connection */
            	e.printStackTrace();
            } finally {
            	dispose();
            }
        }
        
    }
}
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