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.io; 29 30 import java.io.IOException; 31 32 import org.apache.http.util.CharArrayBuffer; 33 34 /** 35 * Session output buffer for blocking connections. This interface is similar to 36 * OutputStream class, but it also provides methods for writing lines of text. 37 * <p> 38 * Implementing classes are also expected to manage intermediate data buffering 39 * for optimal output performance. 40 * 41 * @since 4.0 42 */ 43 public interface SessionOutputBuffer { 44 45 /** 46 * Writes {@code len} bytes from the specified byte array 47 * starting at offset {@code off} to this session buffer. 48 * <p> 49 * If {@code off} is negative, or {@code len} is negative, or 50 * {@code off+len} is greater than the length of the array 51 * {@code b}, then an {@code IndexOutOfBoundsException} is thrown. 52 * 53 * @param b the data. 54 * @param off the start offset in the data. 55 * @param len the number of bytes to write. 56 * @throws IOException if an I/O error occurs. 57 */ 58 void write(byte[] b, int off, int len) throws IOException; 59 60 /** 61 * Writes {@code b.length} bytes from the specified byte array 62 * to this session buffer. 63 * 64 * @param b the data. 65 * @throws IOException if an I/O error occurs. 66 */ 67 void write(byte[] b) throws IOException; 68 69 /** 70 * Writes the specified byte to this session buffer. 71 * 72 * @param b the {@code byte}. 73 * @throws IOException if an I/O error occurs. 74 */ 75 void write(int b) throws IOException; 76 77 /** 78 * Writes characters from the specified string followed by a line delimiter 79 * to this session buffer. 80 * <p> 81 * The choice of a char encoding and line delimiter sequence is up to the 82 * specific implementations of this interface. 83 * 84 * @param s the line. 85 * @throws IOException if an I/O error occurs. 86 */ 87 void writeLine(String s) throws IOException; 88 89 /** 90 * Writes characters from the specified char array followed by a line 91 * delimiter to this session buffer. 92 * <p> 93 * The choice of a char encoding and line delimiter sequence is up to the 94 * specific implementations of this interface. 95 * 96 * @param buffer the buffer containing chars of the line. 97 * @throws IOException if an I/O error occurs. 98 */ 99 void writeLine(CharArrayBuffer buffer) throws IOException; 100 101 /** 102 * Flushes this session buffer and forces any buffered output bytes 103 * to be written out. The general contract of {@code flush} is 104 * that calling it is an indication that, if any bytes previously 105 * written have been buffered by the implementation of the output 106 * stream, such bytes should immediately be written to their 107 * intended destination. 108 * 109 * @throws IOException if an I/O error occurs. 110 */ 111 void flush() throws IOException; 112 113 /** 114 * Returns {@link HttpTransportMetrics} for this session buffer. 115 * 116 * @return transport metrics. 117 */ 118 HttpTransportMetrics getMetrics(); 119 120 }