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.nio.reactor; 29 30 import java.io.IOException; 31 32 /** 33 * HttpCore NIO is based on the Reactor pattern as described by Doug Lea. 34 * The purpose of I/O reactors is to react to I/O events and to dispatch event 35 * notifications to individual I/O sessions. The main idea of I/O reactor 36 * pattern is to break away from the one thread per connection model imposed 37 * by the classic blocking I/O model. 38 * <p> 39 * The IOReactor interface represents an abstract object implementing 40 * the Reactor pattern. 41 * <p> 42 * I/O reactors usually employ a small number of dispatch threads (often as 43 * few as one) to dispatch I/O event notifications to a much greater number 44 * (often as many as several thousands) of I/O sessions or connections. It is 45 * generally recommended to have one dispatch thread per CPU core. 46 * 47 * @since 4.0 48 */ 49 public interface IOReactor { 50 51 /** 52 * Returns the current status of the reactor. 53 * 54 * @return reactor status. 55 */ 56 IOReactorStatus getStatus(); 57 58 /** 59 * Starts the reactor and initiates the dispatch of I/O event notifications 60 * to the given {@link IOEventDispatch}. 61 * 62 * @param eventDispatch the I/O event dispatch. 63 * @throws IOException in case of an I/O error. 64 */ 65 void execute(IOEventDispatch eventDispatch) 66 throws IOException; 67 68 /** 69 * Initiates shutdown of the reactor and blocks approximately for the given 70 * period of time in milliseconds waiting for the reactor to terminate all 71 * active connections, to shut down itself and to release system resources 72 * it currently holds. 73 * 74 * @param waitMs wait time in milliseconds. 75 * @throws IOException in case of an I/O error. 76 */ 77 void shutdown(long waitMs) 78 throws IOException; 79 80 /** 81 * Initiates shutdown of the reactor and blocks for a default period of 82 * time waiting for the reactor to terminate all active connections, to shut 83 * down itself and to release system resources it currently holds. It is 84 * up to individual implementations to decide for how long this method can 85 * remain blocked. 86 * 87 * @throws IOException in case of an I/O error. 88 */ 89 void shutdown() 90 throws IOException; 91 92 }