001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.io.output; 018 019import java.io.FilterOutputStream; 020import java.io.IOException; 021import java.io.OutputStream; 022 023import org.apache.commons.io.IOUtils; 024 025/** 026 * OutputStream which breaks larger output blocks into chunks. 027 * Native code may need to copy the input array; if the write buffer 028 * is very large this can cause OOME. 029 * 030 * @since 2.5 031 */ 032public class ChunkedOutputStream extends FilterOutputStream { 033 034 /** 035 * The maximum chunk size to us when writing data arrays 036 */ 037 private final int chunkSize; 038 039 /** 040 * Creates a new stream that uses a chunk size of {@link IOUtils#DEFAULT_BUFFER_SIZE}. 041 * 042 * @param stream the stream to wrap 043 */ 044 public ChunkedOutputStream(final OutputStream stream) { 045 this(stream, IOUtils.DEFAULT_BUFFER_SIZE); 046 } 047 048 /** 049 * Creates a new stream that uses the specified chunk size. 050 * 051 * @param stream the stream to wrap 052 * @param chunkSize the chunk size to use; must be a positive number. 053 * @throws IllegalArgumentException if the chunk size is <= 0 054 */ 055 public ChunkedOutputStream(final OutputStream stream, final int chunkSize) { 056 super(stream); 057 if (chunkSize <= 0) { 058 throw new IllegalArgumentException(); 059 } 060 this.chunkSize = chunkSize; 061 } 062 063 /** 064 * Writes the data buffer in chunks to the underlying stream 065 * 066 * @param data the data to write 067 * @param srcOffset the offset 068 * @param length the length of data to write 069 * 070 * @throws IOException if an I/O error occurs. 071 */ 072 @Override 073 public void write(final byte[] data, final int srcOffset, final int length) throws IOException { 074 int bytes = length; 075 int dstOffset = srcOffset; 076 while(bytes > 0) { 077 final int chunk = Math.min(bytes, chunkSize); 078 out.write(data, dstOffset, chunk); 079 bytes -= chunk; 080 dstOffset += chunk; 081 } 082 } 083 084}