1 /* 2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/impl/io/ContentLengthOutputStream.java $ 3 * $Revision: 560343 $ 4 * $Date: 2007-07-27 11:18:19 -0700 (Fri, 27 Jul 2007) $ 5 * 6 * ==================================================================== 7 * Licensed to the Apache Software Foundation (ASF) under one 8 * or more contributor license agreements. See the NOTICE file 9 * distributed with this work for additional information 10 * regarding copyright ownership. The ASF licenses this file 11 * to you under the Apache License, Version 2.0 (the 12 * "License"); you may not use this file except in compliance 13 * with the License. You may obtain a copy of the License at 14 * 15 * http://www.apache.org/licenses/LICENSE-2.0 16 * 17 * Unless required by applicable law or agreed to in writing, 18 * software distributed under the License is distributed on an 19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 20 * KIND, either express or implied. See the License for the 21 * specific language governing permissions and limitations 22 * under the License. 23 * ==================================================================== 24 * 25 * This software consists of voluntary contributions made by many 26 * individuals on behalf of the Apache Software Foundation. For more 27 * information on the Apache Software Foundation, please see 28 * <http://www.apache.org/>. 29 * 30 */ 31 32 package org.apache.http.impl.io; 33 34 import java.io.IOException; 35 import java.io.OutputStream; 36 37 import org.apache.http.io.SessionOutputBuffer; 38 39 /** 40 * A stream wrapper that closes itself after a defined number of bytes. 41 * 42 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> 43 * 44 * @version $Revision: 560343 $ 45 * 46 * @since 4.0 47 */ 48 public class ContentLengthOutputStream extends OutputStream { 49 50 /** 51 * Wrapped session outbut buffer. 52 */ 53 private final SessionOutputBuffer out; 54 55 /** 56 * The maximum number of bytes that can be written the stream. Subsequent 57 * write operations will be ignored. 58 */ 59 private final long contentLength; 60 61 /** Total bytes written */ 62 private long total = 0; 63 64 /** True if the stream is closed. */ 65 private boolean closed = false; 66 67 /** 68 * Creates a new length limited stream 69 * 70 * @param out The data transmitter to wrap 71 * @param contentLength The maximum number of bytes that can be written to 72 * the stream. Subsequent write operations will be ignored. 73 * 74 * @since 4.0 75 */ ContentLengthOutputStream(final SessionOutputBuffer out, long contentLength)76 public ContentLengthOutputStream(final SessionOutputBuffer out, long contentLength) { 77 super(); 78 if (out == null) { 79 throw new IllegalArgumentException("Session output buffer may not be null"); 80 } 81 if (contentLength < 0) { 82 throw new IllegalArgumentException("Content length may not be negative"); 83 } 84 this.out = out; 85 this.contentLength = contentLength; 86 } 87 88 /** 89 * <p>Does not close the underlying socket output.</p> 90 * 91 * @throws IOException If an I/O problem occurs. 92 */ close()93 public void close() throws IOException { 94 if (!this.closed) { 95 this.closed = true; 96 this.out.flush(); 97 } 98 } 99 flush()100 public void flush() throws IOException { 101 this.out.flush(); 102 } 103 write(byte[] b, int off, int len)104 public void write(byte[] b, int off, int len) throws IOException { 105 if (this.closed) { 106 throw new IOException("Attempted write to closed stream."); 107 } 108 if (this.total < this.contentLength) { 109 long max = this.contentLength - this.total; 110 if (len > max) { 111 len = (int) max; 112 } 113 this.out.write(b, off, len); 114 this.total += len; 115 } 116 } 117 write(byte[] b)118 public void write(byte[] b) throws IOException { 119 write(b, 0, b.length); 120 } 121 write(int b)122 public void write(int b) throws IOException { 123 if (this.closed) { 124 throw new IOException("Attempted write to closed stream."); 125 } 126 if (this.total < this.contentLength) { 127 this.out.write(b); 128 this.total++; 129 } 130 } 131 132 } 133