Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.apache.oozie.compression; import java.io.ByteArrayOutputStream; import java.io.DataInputStream; import java.io.IOException; import java.util.zip.GZIPInputStream; import java.util.zip.GZIPOutputStream; import org.apache.commons.io.IOUtils; /** * Class to compress and decompress data using Gzip codec * */ public class GzipCompressionCodec implements CompressionCodec { public static final String CODEC_NAME = "gz"; public byte[] compressBytes(byte[] header, byte[] data) throws IOException { ByteArrayOutputStream byteOutput = new ByteArrayOutputStream(2000); byteOutput.write(header); GZIPOutputStream gzipOut = new GZIPOutputStream(byteOutput); gzipOut.write(data); gzipOut.close(); return byteOutput.toByteArray(); } public byte[] compressString(byte[] header, String data) throws IOException { ByteArrayOutputStream byteOutput = new ByteArrayOutputStream(1000); byteOutput.write(header); GZIPOutputStream gzipOut = new GZIPOutputStream(byteOutput); gzipOut.write(data.getBytes(CodecFactory.UTF_8_ENCODING)); gzipOut.close(); return byteOutput.toByteArray(); } public String decompressToString(DataInputStream dais) throws IOException { GZIPInputStream gzipIn = new GZIPInputStream(dais); String decompress = IOUtils.toString(gzipIn, CodecFactory.UTF_8_ENCODING); gzipIn.close(); return decompress; } public byte[] decompressToBytes(DataInputStream dais) throws IOException { GZIPInputStream gzipIn = new GZIPInputStream(dais); byte[] decompress = IOUtils.toByteArray(gzipIn); gzipIn.close(); return decompress; } }