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    private long bytesRead = 0;
025
026    /**
027     * Increments the counter of already read bytes.
028     * Doesn't increment if the EOF has been hit (read == -1)
029     *
030     * @param read the number of bytes read
031     *
032     * @since 1.1
033     */
034    protected void count(final int read) {
035        count((long) read);
036    }
037
038    /**
039     * Increments the counter of already read bytes.
040     * Doesn't increment if the EOF has been hit (read == -1)
041     *
042     * @param read the number of bytes read
043     */
044    protected void count(final long read) {
045        if (read != -1) {
046            bytesRead = bytesRead + read;
047        }
048    }
049
050    /**
051     * Decrements the counter of already read bytes.
052     *
053     * @param pushedBack the number of bytes pushed back.
054     * @since 1.7
055     */
056    protected void pushedBackBytes(final long pushedBack) {
057        bytesRead -= pushedBack;
058    }
059
060    /**
061     * Returns the current number of bytes read from this stream.
062     * @return the number of read bytes
063     * @deprecated this method may yield wrong results for large
064     * archives, use #getBytesRead instead
065     */
066    @Deprecated
067    public int getCount() {
068        return (int) bytesRead;
069    }
070
071    /**
072     * Returns the current number of bytes read from this stream.
073     * @return the number of read bytes
074     *
075     * @since 1.1
076     */
077    public long getBytesRead() {
078        return bytesRead;
079    }
080
081    /**
082     * Returns the amount of raw or compressed bytes read by the stream.
083     *
084     * <p>This implementation invokes {@link #getBytesRead}.</p>
085     *
086     * <p>Provides half of {@link
087     * org.apache.commons.compress.utils.InputStreamStatistics}
088     * without forcing subclasses to implement the other half.</p>
089     *
090     * @return the amount of decompressed bytes returned by the stream
091     * @since 1.17
092     */
093    public long getUncompressedCount() {
094        return getBytesRead();
095    }
096}