CompressionStreamFactory.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 hivemall.utils.io;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.Deflater;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.InflaterInputStream;

import javax.annotation.Nonnull;

import org.tukaani.xz.FinishableWrapperOutputStream;
import org.tukaani.xz.LZMA2InputStream;
import org.tukaani.xz.LZMA2Options;
import org.tukaani.xz.UnsupportedOptionsException;
import org.tukaani.xz.XZInputStream;
import org.tukaani.xz.XZOutputStream;

public final class CompressionStreamFactory {
    public static final int DEFAULT_COMPRESSION_LEVEL = -1;

    private CompressionStreamFactory() {}

    public enum CompressionAlgorithm {
        deflate, xz, lzma2;
    }

    public static InputStream createInputStream(@Nonnull final InputStream in,
            @Nonnull final CompressionAlgorithm algo) {
        return createInputStream(in, algo, DEFAULT_COMPRESSION_LEVEL);
    }

    @Nonnull
    public static InputStream createInputStream(@Nonnull final InputStream in,
            @Nonnull final CompressionAlgorithm algo, final int level) {
        switch (algo) {
            case deflate: {
                return new InflaterInputStream(in);
            }
            case xz: {
                try {
                    return new XZInputStream(in);
                } catch (IOException e) {
                    throw new IllegalStateException("Failed to decode by XZ", e);
                }
            }
            case lzma2: {
                final int dictSize;
                if (level == DEFAULT_COMPRESSION_LEVEL) {
                    dictSize = LZMA2Options.DICT_SIZE_DEFAULT; // level 6
                } else {
                    final LZMA2Options options;
                    try {
                        options = new LZMA2Options(level);
                    } catch (UnsupportedOptionsException e) {
                        throw new IllegalStateException("LZMA2Option configuration failed", e);
                    }
                    dictSize = options.getDictSize();
                }
                return new LZMA2InputStream(in, dictSize);
            }
            default:
                throw new UnsupportedOperationException("Unsupported compression algorithm: "
                        + algo);
        }
    }

    @Nonnull
    public static FinishableOutputStream createOutputStream(@Nonnull final OutputStream out,
            @Nonnull final CompressionAlgorithm algo) {
        return createOutputStream(out, algo, DEFAULT_COMPRESSION_LEVEL);
    }

    @Nonnull
    public static FinishableOutputStream createOutputStream(@Nonnull final OutputStream out,
            @Nonnull final CompressionAlgorithm algo, int level) {
        switch (algo) {
            case deflate: {
                final DeflaterOutputStream deflateOut;
                if (level == DEFAULT_COMPRESSION_LEVEL) {
                    deflateOut = new DeflaterOutputStream(out);
                } else {
                    Deflater d = new Deflater(level);
                    deflateOut = new hivemall.utils.io.DeflaterOutputStream(out, d);
                }
                return new FinishableOutputStreamAdapter(deflateOut) {
                    @Override
                    public void finish() throws IOException {
                        deflateOut.finish();
                        deflateOut.flush();
                        IOUtils.finishStream(out);
                    }
                };
            }
            case xz: {
                if (level == DEFAULT_COMPRESSION_LEVEL) {
                    level = LZMA2Options.PRESET_DEFAULT; // level 6
                }
                final LZMA2Options options;
                try {
                    options = new LZMA2Options(level);
                } catch (UnsupportedOptionsException e) {
                    throw new IllegalStateException("LZMA2Option configuration failed", e);
                }
                final XZOutputStream xz;
                try {
                    xz = new XZOutputStream(out, options);
                } catch (IOException e) {
                    throw new IllegalStateException("Failed to encode by XZ", e);
                }
                return new FinishableOutputStreamAdapter(xz) {
                    @Override
                    public void finish() throws IOException {
                        xz.finish();
                        IOUtils.finishStream(out);
                    }
                };
            }
            case lzma2: {
                if (level == DEFAULT_COMPRESSION_LEVEL) {
                    level = LZMA2Options.PRESET_DEFAULT; // level 6
                }
                final LZMA2Options options;
                try {
                    options = new LZMA2Options(level);
                } catch (UnsupportedOptionsException e) {
                    throw new IllegalStateException("LZMA2Option configuration failed", e);
                }
                FinishableWrapperOutputStream wrapped = new FinishableWrapperOutputStream(out);
                final org.tukaani.xz.FinishableOutputStream lzma2 = options.getOutputStream(wrapped);
                return new FinishableOutputStreamAdapter(lzma2) {
                    @Override
                    public void finish() throws IOException {
                        lzma2.finish();
                        IOUtils.finishStream(out);
                    }
                };
            }
            default:
                throw new UnsupportedOperationException("Unsupported compression algorithm: "
                        + algo);
        }
    }
}