Initial commit from SVN.

Common/src/com/common/io/CompressionOutputStream.java

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+/*
+ * Copyright (c) 2003,2009 Declarative Engineering LLC.
+ * All rights reserved.  This program and the accompanying materials
+ * are made available under the terms of the Declarative Engineering LLC
+ * verson 1 which accompanies this distribution, and is available at
+ * http://declarativeengineering.com/legal/DE_Developer_License_v1.txt
+ */
+package com.common.io;
+
+import java.io.OutputStream;
+import java.io.IOException;
+import java.util.zip.*;
+
+public class CompressionOutputStream extends OutputStream implements IOutputStream {
+	public static final int DEFAULT_BUFFER_SIZE = 301;
+	public static final int MAX_BUFFER_SIZE = 65535;
+
+	protected OutputStream stream = null;
+	protected Deflater deflater = null;
+	protected byte[] outputBuffer = null;
+/**
+ * CompressionOutputStream constructor.
+ * @param stream The stream that will handle all output from this stream.
+ */
+public CompressionOutputStream(OutputStream stream) {
+	this(stream, null, DEFAULT_BUFFER_SIZE);
+}//CompressionOutputStream()//
+/**
+ * CompressionOutputStream constructor.
+ * @param stream The stream that will handle all output from this stream.
+ * @param deflater The deflater to be used.
+ */
+public CompressionOutputStream(OutputStream stream, Deflater deflater) {
+	this(stream, deflater, DEFAULT_BUFFER_SIZE);
+}//CompressionOutputStream()//
+/**
+ * CompressionOutputStream constructor.
+ * @param stream The stream that will handle all output from this stream.
+ * @param deflater The deflater to be used.
+ * @param bufferSize The size of the buffer used to read from the deflater.
+ */
+public CompressionOutputStream(OutputStream stream, Deflater deflater, int bufferSize) {
+	//Validate the inputs.//
+	if(bufferSize < 1) {
+		throw new IllegalArgumentException("Buffer size must be greater than zero.");
+	}//if//
+	else if(bufferSize > MAX_BUFFER_SIZE) {
+		throw new IllegalArgumentException("Buffer size must be less than " + MAX_BUFFER_SIZE + ".");
+	}//else if//
+	else if(stream == null) {
+		throw new IllegalArgumentException("A non-null output stream must be provided.");
+	}//else if//
+	else if(deflater == null) {
+		deflater = new Deflater(Deflater.DEFAULT_COMPRESSION, true);
+	}//else if//
+
+	this.stream = stream;
+	this.deflater = deflater;
+	this.outputBuffer = new byte[bufferSize];
+}//CompressionOutputStream()//
+/* (non-Javadoc)
+ * @see java.io.IOutputStream#canEncrypt()
+ */
+public boolean canEncrypt() {
+	return (stream instanceof IOutputStream) && (((IOutputStream) stream).canEncrypt());
+}//canEncrypt()//
+/* (non-Javadoc)
+ * @see java.io.OutputStream#close()
+ */
+public void close() throws IOException {
+	deflater.finish();
+	deflate();
+	
+	super.close();
+}//close()//
+/**
+ * Deflates the cached data.
+ */
+private void deflate() throws IOException {
+	int count = 0;
+	
+	while((count = deflater.deflate(outputBuffer, 2, outputBuffer.length - 2)) > 0) {
+		StreamSupport.writeShort((short) count, outputBuffer, 0);  //Note: count should never exceed the buffer length and thus should stay within two bytes in size.//
+		stream.write(outputBuffer, 0, count + 2);
+	}//while//
+	
+	/* Another way of doing the same thing I think.
+	while(!deflater.needsInput()) {
+		int count = deflater.deflate(outputBuffer);
+
+		if(count > 0) {
+			stream.write(outputBuffer, 0, count);
+		}//if//
+	}//while//
+	*/
+}//deflate()//
+/* (non-Javadoc)
+ * @see java.io.IOutputStream#encrypt(boolean)
+ */
+public void encrypt(boolean encrypt) throws IOException {
+	if(stream instanceof IOutputStream) {
+		if(((IOutputStream) stream).canEncrypt()) {
+			flush();
+			((IOutputStream) stream).encrypt(encrypt);
+		}//if//
+		else {
+			throw new IOException(ERROR_ENCRYPTION_NOT_SUPPORTED);
+		}//else//
+	}//if//
+	else {
+		throw new IOException(ERROR_ENCRYPTION_NOT_SUPPORTED);
+	}//else//
+}//encrypt()//
+/* (non-Javadoc)
+ * @see java.io.OutputStream#flush()
+ */
+public void flush() throws IOException {
+	if(deflater.getTotalIn() > 0) {
+		deflater.finish();
+		deflate();
+		deflater.reset();
+	}//if//
+		
+	stream.flush();
+}//flush()//
+/* (non-Javadoc)
+ * @see java.io.IOutputStream#isEncrypting()
+ */
+public boolean isEncrypting() {
+	return (stream instanceof IOutputStream) && (((IOutputStream) stream).isEncrypting());
+}//isEncrypting()//
+/* (non-Javadoc)
+ * @see java.io.OutputStream#write(byte[])
+ */
+public void write(byte[] buffer) throws IOException {
+	write(buffer, 0, buffer.length);
+}//write()//
+/* (non-Javadoc)
+ * @see java.io.OutputStream#write(byte[], int, int)
+ */
+public void write(byte[] buffer, int offset, int length) throws IOException {
+	deflater.setInput(buffer, offset, length);
+	deflate();
+}//write()//
+/* (non-Javadoc)
+ * @see java.io.OutputStream#write(int)
+ */
+public void write(int b) throws IOException {
+	outputBuffer[0] = (byte) (b & 0xFF);
+	write(outputBuffer, 0, 1);
+}//write()//
+}//CompressionOutputStream//