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.commons.compress.compressors.pack200; import java.io.IOException; import java.io.OutputStream; import java.util.Map; import java.util.jar.JarInputStream; import java.util.jar.Pack200; import org.apache.commons.compress.compressors.CompressorOutputStream; import org.apache.commons.compress.utils.IOUtils; /** * An output stream that compresses using the Pack200 format. * * @NotThreadSafe * @since 1.3 */ public class Pack200CompressorOutputStream extends CompressorOutputStream { private boolean finished = false; private final OutputStream originalOutput; private final StreamBridge streamBridge; private final Map<String, String> properties; /** * Compresses the given stream, caching the compressed data in * memory. * * @param out the stream to write to * @throws IOException if writing fails */ public Pack200CompressorOutputStream(final OutputStream out) throws IOException { this(out, Pack200Strategy.IN_MEMORY); } /** * Compresses the given stream using the given strategy to cache * the results. * * @param out the stream to write to * @param mode the strategy to use * @throws IOException if writing fails */ public Pack200CompressorOutputStream(final OutputStream out, final Pack200Strategy mode) throws IOException { this(out, mode, null); } /** * Compresses the given stream, caching the compressed data in * memory and using the given properties. * * @param out the stream to write to * @param props Pack200 properties to use * @throws IOException if writing fails */ public Pack200CompressorOutputStream(final OutputStream out, final Map<String, String> props) throws IOException { this(out, Pack200Strategy.IN_MEMORY, props); } /** * Compresses the given stream using the given strategy to cache * the results and the given properties. * * @param out the stream to write to * @param mode the strategy to use * @param props Pack200 properties to use * @throws IOException if writing fails */ public Pack200CompressorOutputStream(final OutputStream out, final Pack200Strategy mode, final Map<String, String> props) throws IOException { originalOutput = out; streamBridge = mode.newStreamBridge(); properties = props; } @Override public void write(final int b) throws IOException { streamBridge.write(b); } @Override public void write(final byte[] b) throws IOException { streamBridge.write(b); } @Override public void write(final byte[] b, final int from, final int length) throws IOException { streamBridge.write(b, from, length); } @Override public void close() throws IOException { finish(); try { streamBridge.stop(); } finally { originalOutput.close(); } } public void finish() throws IOException { if (!finished) { finished = true; final Pack200.Packer p = Pack200.newPacker(); if (properties != null) { p.properties().putAll(properties); } try (JarInputStream ji = new JarInputStream(streamBridge.getInput())) { p.pack(ji, originalOutput); } } } }