1 /* 2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/impl/io/AbstractSessionOutputBuffer.java $ 3 * $Revision: 652091 $ 4 * $Date: 2008-04-29 13:41:07 -0700 (Tue, 29 Apr 2008) $ 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 import org.apache.http.io.HttpTransportMetrics; 39 import org.apache.http.params.HttpParams; 40 import org.apache.http.params.HttpProtocolParams; 41 import org.apache.http.protocol.HTTP; 42 import org.apache.http.util.ByteArrayBuffer; 43 import org.apache.http.util.CharArrayBuffer; 44 45 /** 46 * Abstract base class for session output buffers that stream data 47 * to an {@link OutputStream}. 48 * 49 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> 50 * 51 */ 52 public abstract class AbstractSessionOutputBuffer implements SessionOutputBuffer { 53 54 private static final byte[] CRLF = new byte[] {HTTP.CR, HTTP.LF}; 55 56 private static final int MAX_CHUNK = 256; 57 58 private OutputStream outstream; 59 private ByteArrayBuffer buffer; 60 61 private String charset = HTTP.US_ASCII; 62 private boolean ascii = true; 63 64 private HttpTransportMetricsImpl metrics; 65 66 protected void init(final OutputStream outstream, int buffersize, final HttpParams params) { 67 if (outstream == null) { 68 throw new IllegalArgumentException("Input stream may not be null"); 69 } 70 if (buffersize <= 0) { 71 throw new IllegalArgumentException("Buffer size may not be negative or zero"); 72 } 73 if (params == null) { 74 throw new IllegalArgumentException("HTTP parameters may not be null"); 75 } 76 this.outstream = outstream; 77 this.buffer = new ByteArrayBuffer(buffersize); 78 this.charset = HttpProtocolParams.getHttpElementCharset(params); 79 this.ascii = this.charset.equalsIgnoreCase(HTTP.US_ASCII) 80 || this.charset.equalsIgnoreCase(HTTP.ASCII); 81 this.metrics = new HttpTransportMetricsImpl(); 82 } 83 84 protected void flushBuffer() throws IOException { 85 int len = this.buffer.length(); 86 if (len > 0) { 87 this.outstream.write(this.buffer.buffer(), 0, len); 88 this.buffer.clear(); 89 this.metrics.incrementBytesTransferred(len); 90 } 91 } 92 93 public void flush() throws IOException { 94 flushBuffer(); 95 this.outstream.flush(); 96 } 97 98 public void write(final byte[] b, int off, int len) throws IOException { 99 if (b == null) { 100 return; 101 } 102 // Do not want to buffer largish chunks 103 // if the byte array is larger then MAX_CHUNK 104 // write it directly to the output stream 105 if (len > MAX_CHUNK || len > this.buffer.capacity()) { 106 // flush the buffer 107 flushBuffer(); 108 // write directly to the out stream 109 this.outstream.write(b, off, len); 110 this.metrics.incrementBytesTransferred(len); 111 } else { 112 // Do not let the buffer grow unnecessarily 113 int freecapacity = this.buffer.capacity() - this.buffer.length(); 114 if (len > freecapacity) { 115 // flush the buffer 116 flushBuffer(); 117 } 118 // buffer 119 this.buffer.append(b, off, len); 120 } 121 } 122 123 public void write(final byte[] b) throws IOException { 124 if (b == null) { 125 return; 126 } 127 write(b, 0, b.length); 128 } 129 130 public void write(int b) throws IOException { 131 if (this.buffer.isFull()) { 132 flushBuffer(); 133 } 134 this.buffer.append(b); 135 } 136 137 public void writeLine(final String s) throws IOException { 138 if (s == null) { 139 return; 140 } 141 if (s.length() > 0) { 142 write(s.getBytes(this.charset)); 143 } 144 write(CRLF); 145 } 146 147 public void writeLine(final CharArrayBuffer s) throws IOException { 148 if (s == null) { 149 return; 150 } 151 if (this.ascii) { 152 int off = 0; 153 int remaining = s.length(); 154 while (remaining > 0) { 155 int chunk = this.buffer.capacity() - this.buffer.length(); 156 chunk = Math.min(chunk, remaining); 157 if (chunk > 0) { 158 this.buffer.append(s, off, chunk); 159 } 160 if (this.buffer.isFull()) { 161 flushBuffer(); 162 } 163 off += chunk; 164 remaining -= chunk; 165 } 166 } else { 167 // This is VERY memory inefficient, BUT since non-ASCII charsets are 168 // NOT meant to be used anyway, there's no point optimizing it 169 byte[] tmp = s.toString().getBytes(this.charset); 170 write(tmp); 171 } 172 write(CRLF); 173 } 174 175 public HttpTransportMetrics getMetrics() { 176 return this.metrics; 177 } 178 179 } 180
