001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.commons.compress.compressors.deflate;
020
021import java.io.IOException;
022import java.io.OutputStream;
023import java.util.zip.Deflater;
024import java.util.zip.DeflaterOutputStream;
025
026import org.apache.commons.compress.compressors.CompressorOutputStream;
027
028/**
029 * Deflate compressor.
030 * @since 1.9
031 */
032public class DeflateCompressorOutputStream extends CompressorOutputStream {
033    private final DeflaterOutputStream out;
034    private final Deflater deflater;
035
036    /**
037     * Creates a Deflate compressed output stream with the default parameters.
038     * @param outputStream the stream to wrap
039     * @throws IOException on error
040     */
041    public DeflateCompressorOutputStream(final OutputStream outputStream) throws IOException {
042        this(outputStream, new DeflateParameters());
043    }
044
045    /**
046     * Creates a Deflate compressed output stream with the specified parameters.
047     * @param outputStream the stream to wrap
048     * @param parameters the deflate parameters to apply
049     * @throws IOException on error
050     */
051    public DeflateCompressorOutputStream(final OutputStream outputStream,
052                                         final DeflateParameters parameters) throws IOException {
053        this.deflater = new Deflater(parameters.getCompressionLevel(), !parameters.withZlibHeader());
054        this.out = new DeflaterOutputStream(outputStream, deflater);
055    }
056
057    @Override
058    public void write(final int b) throws IOException {
059        out.write(b);
060    }
061
062    @Override
063    public void write(final byte[] buf, final int off, final int len) throws IOException {
064        out.write(buf, off, len);
065    }
066
067    /**
068     * Flushes the encoder and calls <code>outputStream.flush()</code>.
069     * All buffered pending data will then be decompressible from
070     * the output stream. Calling this function very often may increase
071     * the compressed file size a lot.
072     */
073    @Override
074    public void flush() throws IOException {
075        out.flush();
076    }
077
078    /**
079     * Finishes compression without closing the underlying stream.
080     * <p>No more data can be written to this stream after finishing.</p>
081     * @throws IOException on error
082     */
083    public void finish() throws IOException {
084        out.finish();
085    }
086
087    @Override
088    public void close() throws IOException {
089        try {
090            out.close();
091        } finally {
092            deflater.end();
093        }
094    }
095}