org.igniterealtime.jbosh.ZLIBCodec Maven / Gradle / Ivy
/*
* Copyright 2009 Mike Cumings
*
* 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.igniterealtime.jbosh;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.InflaterInputStream;
/**
* Codec methods for compressing and uncompressing using ZLIB.
*/
final class ZLIBCodec {
/**
* Size of the internal buffer when decoding.
*/
private static final int BUFFER_SIZE = 512;
///////////////////////////////////////////////////////////////////////////
// Constructors:
/**
* Prevent construction.
*/
private ZLIBCodec() {
// Empty
}
/**
* Returns the name of the codec.
*
* @return string name of the codec (i.e., "deflate")
*/
public static String getID() {
return "deflate";
}
/**
* Compress/encode the data provided using the ZLIB format.
*
* @param data data to compress
* @return compressed data
* @throws IOException on compression failure
*/
public static byte[] encode(final byte[] data) throws IOException {
ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
DeflaterOutputStream deflateOut = null;
try {
deflateOut = new DeflaterOutputStream(byteOut);
deflateOut.write(data);
deflateOut.close();
byteOut.close();
return byteOut.toByteArray();
} finally {
deflateOut.close();
byteOut.close();
}
}
/**
* Uncompress/decode the data provided using the ZLIB format.
*
* @param data data to uncompress
* @return uncompressed data
* @throws IOException on decompression failure
*/
public static byte[] decode(final byte[] compressed) throws IOException {
ByteArrayInputStream byteIn = new ByteArrayInputStream(compressed);
ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
InflaterInputStream inflaterIn = null;
try {
inflaterIn = new InflaterInputStream(byteIn);
int read;
byte[] buffer = new byte[BUFFER_SIZE];
do {
read = inflaterIn.read(buffer);
if (read > 0) {
byteOut.write(buffer, 0, read);
}
} while (read >= 0);
return byteOut.toByteArray();
} finally {
inflaterIn.close();
byteOut.close();
}
}
}