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;
020
021import java.io.InputStream;
022
023public abstract class CompressorInputStream extends InputStream {
024
025    private long bytesRead;
026
027    /**
028     * Constructs a new instance.
029     */
030    public CompressorInputStream() {
031        // empty
032    }
033
034    /**
035     * Increments the counter of already read bytes. Doesn't increment if the EOF has been hit (read == -1)
036     *
037     * @param read the number of bytes read
038     *
039     * @since 1.1
040     */
041    protected void count(final int read) {
042        count((long) read);
043    }
044
045    /**
046     * Increments the counter of already read bytes. Doesn't increment if the EOF has been hit (read == -1)
047     *
048     * @param read the number of bytes read
049     */
050    protected void count(final long read) {
051        if (read != -1) {
052            bytesRead += read;
053        }
054    }
055
056    /**
057     * Gets the current number of bytes read from this stream.
058     *
059     * @return the number of read bytes
060     *
061     * @since 1.1
062     */
063    public long getBytesRead() {
064        return bytesRead;
065    }
066
067    /**
068     * Gets the current number of bytes read from this stream.
069     *
070     * @return the number of read bytes
071     * @deprecated this method may yield wrong results for large archives, use #getBytesRead instead
072     */
073    @Deprecated
074    public int getCount() {
075        return (int) bytesRead;
076    }
077
078    /**
079     * Gets the amount of raw or compressed bytes read by the stream.
080     *
081     * <p>
082     * This implementation invokes {@link #getBytesRead}.
083     * </p>
084     *
085     * <p>
086     * Provides half of {@link org.apache.commons.compress.utils.InputStreamStatistics} without forcing subclasses to implement the other half.
087     * </p>
088     *
089     * @return the amount of decompressed bytes returned by the stream
090     * @since 1.17
091     */
092    public long getUncompressedCount() {
093        return getBytesRead();
094    }
095
096    /**
097     * Decrements the counter of already read bytes.
098     *
099     * @param pushedBack the number of bytes pushed back.
100     * @since 1.7
101     */
102    protected void pushedBackBytes(final long pushedBack) {
103        bytesRead -= pushedBack;
104    }
105}