examples/bundles/org.eclipse.ecf.example.collab/src/org/eclipse/ecf/example/collab/share/io/SharedObjectOutputStream.java

/****************************************************************************
 * Copyright (c) 2004 Composent, Inc. and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Composent, Inc. - initial API and implementation
 *****************************************************************************/

package org.eclipse.ecf.example.collab.share.io;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.zip.GZIPOutputStream;

public class SharedObjectOutputStream extends OutputStream {
	public static final int DEFAULT_BUFF_SIZE = 900;
	public static final boolean DEFAULT_COMPRESSION = true;

	protected StreamSender sender;
	protected ByteArrayOutputStream outputStream;
	protected GZIPOutputStream compressor;
	protected int defaultLength;
	protected int bytesSentCount = 0;
	protected boolean useCompression;

	public SharedObjectOutputStream(StreamSender sender, int size,
			boolean compression) throws IOException {
		this.sender = sender;
		this.defaultLength = size;
		this.useCompression = compression;
		resetStreams();
	}

	public SharedObjectOutputStream(StreamSender obj) throws IOException {
		this(obj, DEFAULT_BUFF_SIZE, DEFAULT_COMPRESSION);
	}

	public SharedObjectOutputStream(StreamSender obj, int size)
			throws IOException {
		this(obj, size, DEFAULT_COMPRESSION);
	}

	public SharedObjectOutputStream(StreamSender obj, boolean compression)
			throws IOException {
		this(obj, DEFAULT_BUFF_SIZE, compression);
	}

	protected void resetStreams() throws IOException {
		outputStream = new ByteArrayOutputStream(defaultLength);
		if (useCompression)
			compressor = new GZIPOutputStream(outputStream);
	}

	public void close() throws IOException {
		if (useCompression) {
			compressor.close();
		} else
			outputStream.close();
	}

	public void flush() throws IOException {
		sendMsgAndResetStream();
	}

	protected final void sendMsgAndResetStream() throws IOException {
		if (useCompression) {
			compressor.flush();
			compressor.finish();
		} else
			outputStream.flush();
		// Actually ask our StreamSender to send msg with count of size and data
		sender.sendDataMsg(bytesSentCount, outputStream.toByteArray());
		resetStreams();
		bytesSentCount = 0;
	}

	public void write(int a) throws IOException {
		if (bytesSentCount >= defaultLength) {
			sendMsgAndResetStream();
		}
		bytesSentCount++;
		streamWrite(a);
	}

	protected void streamWrite(int a) throws IOException {
		if (useCompression) {
			compressor.write(a);
		} else
			outputStream.write(a);
	}
}