1 /* 2 * ==================================================================== 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * ==================================================================== 20 * 21 * This software consists of voluntary contributions made by many 22 * individuals on behalf of the Apache Software Foundation. For more 23 * information on the Apache Software Foundation, please see 24 * <http://www.apache.org/>. 25 * 26 */ 27 28 package org.apache.http.impl.io; 29 30 import java.io.IOException; 31 import java.io.OutputStream; 32 33 import org.apache.http.io.SessionOutputBuffer; 34 import org.apache.http.util.Args; 35 36 /** 37 * Output stream that writes data without any transformation. The end of 38 * the content entity is demarcated by closing the underlying connection 39 * (EOF condition). Entities transferred using this input stream can be of 40 * unlimited length. 41 * <p> 42 * Note that this class NEVER closes the underlying stream, even when close 43 * gets called. Instead, the stream will be marked as closed and no further 44 * output will be permitted. 45 * 46 * @since 4.0 47 */ 48 public class IdentityOutputStream extends OutputStream { 49 50 /** 51 * Wrapped session output buffer. 52 */ 53 private final SessionOutputBuffer out; 54 55 /** True if the stream is closed. */ 56 private boolean closed = false; 57 58 public IdentityOutputStream(final SessionOutputBuffer out) { 59 super(); 60 this.out = Args.notNull(out, "Session output buffer"); 61 } 62 63 /** 64 * <p>Does not close the underlying socket output.</p> 65 * 66 * @throws IOException If an I/O problem occurs. 67 */ 68 @Override 69 public void close() throws IOException { 70 if (!this.closed) { 71 this.closed = true; 72 this.out.flush(); 73 } 74 } 75 76 @Override 77 public void flush() throws IOException { 78 this.out.flush(); 79 } 80 81 @Override 82 public void write(final byte[] b, final int off, final int len) throws IOException { 83 if (this.closed) { 84 throw new IOException("Attempted write to closed stream."); 85 } 86 this.out.write(b, off, len); 87 } 88 89 @Override 90 public void write(final byte[] b) throws IOException { 91 write(b, 0, b.length); 92 } 93 94 @Override 95 public void write(final int b) throws IOException { 96 if (this.closed) { 97 throw new IOException("Attempted write to closed stream."); 98 } 99 this.out.write(b); 100 } 101 102 }