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.utils;
020
021import java.io.FilterOutputStream;
022import java.io.IOException;
023import java.io.OutputStream;
024
025/**
026 * Stream that tracks the number of bytes read.
027 * @since 1.3
028 * @NotThreadSafe
029 */
030public class CountingOutputStream extends FilterOutputStream {
031    private long bytesWritten;
032
033    public CountingOutputStream(final OutputStream out) {
034        super(out);
035    }
036
037    @Override
038    public void write(final int b) throws IOException {
039        out.write(b);
040        count(1);
041    }
042    @Override
043    public void write(final byte[] b) throws IOException {
044        write(b, 0, b.length);
045    }
046    @Override
047    public void write(final byte[] b, final int off, final int len) throws IOException {
048        out.write(b, off, len);
049        count(len);
050    }
051
052    /**
053     * Increments the counter of already written bytes.
054     * Doesn't increment if the EOF has been hit (written == -1)
055     *
056     * @param written the number of bytes written
057     */
058    protected void count(final long written) {
059        if (written != -1) {
060            bytesWritten += written;
061        }
062    }
063
064    /**
065     * Returns the current number of bytes written to this stream.
066     * @return the number of written bytes
067     */
068    public long getBytesWritten() {
069        return bytesWritten;
070    }
071}