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.FilterInputStream; 022import java.io.IOException; 023import java.io.InputStream; 024 025/** 026 * Stream that tracks the number of bytes read. 027 * @since 1.3 028 * @NotThreadSafe 029 */ 030public 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 final int r = in.read(); 040 if (r >= 0) { 041 count(1); 042 } 043 return r; 044 } 045 @Override 046 public int read(final byte[] b) throws IOException { 047 return read(b, 0, b.length); 048 } 049 @Override 050 public int read(final byte[] b, final int off, final int len) throws IOException { 051 final 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(final 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}