    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     */
    019    package org.apache.commons.compress.utils;
    020
    021    import java.io.FilterInputStream;
    022    import java.io.IOException;
    023    import java.io.InputStream;
    024
    025    /**
    026     * Stream that tracks the number of bytes read.
    027     * @since Apache Commons Compress 1.3
    028     * @NotThreadSafe
    029     */
    030    public class CountingInputStream extends FilterInputStream {
    031        private long bytesRead;
    032
    033        public CountingInputStream(final InputStream in) {
    034            super(in);
    035        }
    036
    037        @Override
    038        public int read() throws IOException {
    039            int r = in.read();
    040            if (r >= 0) {
    041                count(1);
    042            }
    043            return r;
    044        }
    045        @Override
    046        public int read(byte[] b) throws IOException {
    047            return read(b, 0, b.length);
    048        }
    049        @Override
    050        public int read(byte[] b, int off, int len) throws IOException {
    051            int r = in.read(b, off, len);
    052            if (r >= 0) {
    053                count(r);
    054            }
    055            return r;
    056        }
    057        /**
    058         * Increments the counter of already read bytes.
    059         * Doesn't increment if the EOF has been hit (read == -1)
    060         *
    061         * @param read the number of bytes read
    062         */
    063        protected final void count(long read) {
    064            if (read != -1) {
    065                bytesRead += read;
    066            }
    067        }
    068
    069        /**
    070         * Returns the current number of bytes read from this stream.
    071         * @return the number of read bytes
    072         */
    073        public long getBytesRead() {
    074            return bytesRead;
    075        }
    076    }