    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.compress.compressors.zstandard;
    019
    020
    021import java.io.IOException;
    022import java.io.InputStream;
    023
    024import org.apache.commons.compress.compressors.CompressorInputStream;
    025import org.apache.commons.compress.utils.CountingInputStream;
    026import org.apache.commons.compress.utils.IOUtils;
    027import org.apache.commons.compress.utils.InputStreamStatistics;
    028
    029import com.github.luben.zstd.BufferPool;
    030import com.github.luben.zstd.ZstdInputStream;
    031
    032/**
    033 * {@link CompressorInputStream} implementation to decode Zstandard encoded stream.
    034 * Library relies on <a href="https://github.com/luben/zstd-jni/">Zstandard JNI</a>
    035 *
    036 * @since 1.16
    037 */
    038public class ZstdCompressorInputStream extends CompressorInputStream
    039    implements InputStreamStatistics {
    040
    041    private final CountingInputStream countingStream;
    042    private final ZstdInputStream decIS;
    043
    044    public ZstdCompressorInputStream(final InputStream in) throws IOException {
    045        this.decIS = new ZstdInputStream(countingStream = new CountingInputStream(in));
    046    }
    047
    048    /**
    049     * Creates a new input stream that decompresses zstd-compressed data from
    050     * the specific input stream
    051     *
    052     * @param in the input stream of compressed data
    053     * @param bufferPool a configuration of zstd-jni that allows users to customize
    054     *                   how buffers are recycled. Either a
    055     *                   {@link com.github.luben.zstd.NoPool} or a
    056     *                   {@link com.github.luben.zstd.RecyclingBufferPool} is
    057     *                   allowed here.
    058     * @throws IOException if an IO error occurs.
    059     */
    060    public ZstdCompressorInputStream(final InputStream in, final BufferPool bufferPool) throws IOException {
    061        this.decIS = new ZstdInputStream(countingStream = new CountingInputStream(in), bufferPool);
    062    }
    063
    064    @Override
    065    public int available() throws IOException {
    066        return decIS.available();
    067    }
    068
    069    @Override
    070    public void close() throws IOException {
    071        decIS.close();
    072    }
    073
    074    /**
    075     * @since 1.17
    076     */
    077    @Override
    078    public long getCompressedCount() {
    079        return countingStream.getBytesRead();
    080    }
    081
    082    @Override
    083    public synchronized void mark(final int readlimit) {
    084        decIS.mark(readlimit);
    085    }
    086
    087    @Override
    088    public boolean markSupported() {
    089        return decIS.markSupported();
    090    }
    091
    092    @Override
    093    public int read() throws IOException {
    094        final int ret = decIS.read();
    095        count(ret == -1 ? 0 : 1);
    096        return ret;
    097    }
    098
    099    @Override
    100    public int read(final byte[] b) throws IOException {
    101        return read(b, 0, b.length);
    102    }
    103
    104    @Override
    105    public int read(final byte[] buf, final int off, final int len) throws IOException {
    106        if (len == 0) {
    107            return 0;
    108        }
    109        final int ret = decIS.read(buf, off, len);
    110        count(ret);
    111        return ret;
    112    }
    113
    114    @Override
    115    public synchronized void reset() throws IOException {
    116        decIS.reset();
    117    }
    118
    119    @Override
    120    public long skip(final long n) throws IOException {
    121        return IOUtils.skip(decIS, n);
    122    }
    123
    124    @Override
    125    public String toString() {
    126        return decIS.toString();
    127    }
    128}