Pack200CompressorOutputStream.java

/*
 * 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 org.apache.commons.compress.compressors.CompressorOutputStream;
import org.apache.commons.compress.java.util.jar.Pack200;

/**
 * An output stream that compresses using the Pack200 format.
 *
 * @NotThreadSafe
 * @since 1.3
 */
public class Pack200CompressorOutputStream extends CompressorOutputStream<OutputStream> {
    private boolean finished;
    private final AbstractStreamBridge abstractStreamBridge;
    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, 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.
     *
     * @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 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 {
        super(out);
        abstractStreamBridge = mode.newStreamBridge();
        properties = props;
    }

    @Override
    public void close() throws IOException {
        try {
            finish();
        } finally {
            try {
                abstractStreamBridge.stop();
            } finally {
                out.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(abstractStreamBridge.getInputStream())) {
                p.pack(ji, out);
            }
        }
    }

    @Override
    public void write(final byte[] b) throws IOException {
        abstractStreamBridge.write(b);
    }

    @Override
    public void write(final byte[] b, final int from, final int length) throws IOException {
        abstractStreamBridge.write(b, from, length);
    }

    @Override
    public void write(final int b) throws IOException {
        abstractStreamBridge.write(b);
    }
}