    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
    020import java.io.IOException;
    021import java.io.InputStream;
    022
    023import org.apache.commons.compress.compressors.CompressorInputStream;
    024import org.apache.commons.compress.utils.InputStreamStatistics;
    025import org.apache.commons.io.input.BoundedInputStream;
    026
    027import com.github.luben.zstd.BufferPool;
    028import com.github.luben.zstd.ZstdInputStream;
    029
    030/**
    031 * {@link CompressorInputStream} implementation to decode Zstandard encoded stream. Library relies on <a href="https://github.com/luben/zstd-jni/">Zstandard
    032 * JNI</a>
    033 *
    034 * @since 1.16
    035 */
    036public class ZstdCompressorInputStream extends CompressorInputStream implements InputStreamStatistics {
    037
    038    private final BoundedInputStream countingStream;
    039    private final ZstdInputStream decIS;
    040
    041    public ZstdCompressorInputStream(final InputStream in) throws IOException {
    042        this.decIS = new ZstdInputStream(countingStream = BoundedInputStream.builder().setInputStream(in).get());
    043    }
    044
    045    /**
    046     * Creates a new input stream that decompresses zstd-compressed data from the specific input stream
    047     *
    048     * @param in         the input stream of compressed data
    049     * @param bufferPool a configuration of zstd-jni that allows users to customize how buffers are recycled. Either a {@link com.github.luben.zstd.NoPool} or a
    050     *                   {@link com.github.luben.zstd.RecyclingBufferPool} is allowed here.
    051     * @throws IOException if an IO error occurs.
    052     */
    053    public ZstdCompressorInputStream(final InputStream in, final BufferPool bufferPool) throws IOException {
    054        this.decIS = new ZstdInputStream(countingStream = BoundedInputStream.builder().setInputStream(in).get(), bufferPool);
    055    }
    056
    057    @Override
    058    public int available() throws IOException {
    059        return decIS.available();
    060    }
    061
    062    @Override
    063    public void close() throws IOException {
    064        decIS.close();
    065    }
    066
    067    /**
    068     * @since 1.17
    069     */
    070    @Override
    071    public long getCompressedCount() {
    072        return countingStream.getCount();
    073    }
    074
    075    @Override
    076    public synchronized void mark(final int readLimit) {
    077        decIS.mark(readLimit);
    078    }
    079
    080    @Override
    081    public boolean markSupported() {
    082        return decIS.markSupported();
    083    }
    084
    085    @Override
    086    public int read() throws IOException {
    087        final int ret = decIS.read();
    088        count(ret == -1 ? 0 : 1);
    089        return ret;
    090    }
    091
    092    @Override
    093    public int read(final byte[] b) throws IOException {
    094        return read(b, 0, b.length);
    095    }
    096
    097    @Override
    098    public int read(final byte[] buf, final int off, final int len) throws IOException {
    099        if (len == 0) {
    100            return 0;
    101        }
    102        final int ret = decIS.read(buf, off, len);
    103        count(ret);
    104        return ret;
    105    }
    106
    107    @Override
    108    public synchronized void reset() throws IOException {
    109        decIS.reset();
    110    }
    111
    112    @Override
    113    public long skip(final long n) throws IOException {
    114        return org.apache.commons.io.IOUtils.skip(decIS, n);
    115    }
    116
    117    @Override
    118    public String toString() {
    119        return decIS.toString();
    120    }
    121}