001/* 002 * ==================================================================== 003 * Licensed to the Apache Software Foundation (ASF) under one 004 * or more contributor license agreements. See the NOTICE file 005 * distributed with this work for additional information 006 * regarding copyright ownership. The ASF licenses this file 007 * to you under the Apache License, Version 2.0 (the 008 * "License"); you may not use this file except in compliance 009 * with the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, 014 * software distributed under the License is distributed on an 015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 016 * KIND, either express or implied. See the License for the 017 * specific language governing permissions and limitations 018 * under the License. 019 * ==================================================================== 020 * 021 * This software consists of voluntary contributions made by many 022 * individuals on behalf of the Apache Software Foundation. For more 023 * information on the Apache Software Foundation, please see 024 * <http://www.apache.org/>. 025 * 026 */ 027 028package org.apache.http.nio.protocol; 029 030import java.io.IOException; 031 032import org.apache.http.HttpException; 033import org.apache.http.HttpRequest; 034import org.apache.http.protocol.HttpContext; 035 036/** 037 * {@code HttpAsyncRequestHandler} represents a routine for asynchronous 038 * processing of a specific group of non-blocking HTTP requests. Protocol 039 * handlers are designed to take care of protocol specific aspects, whereas 040 * individual request handlers are expected to take care of application 041 * specific HTTP processing. The main purpose of a request handler is to 042 * generate a response object with a content entity to be sent back to 043 * the client in response to the given request. 044 * 045 * @since 4.2 046 */ 047public interface HttpAsyncRequestHandler<T> { 048 049 /** 050 * Triggered when an incoming request is received. This method should 051 * return a {@link HttpAsyncRequestConsumer} that will be used to process 052 * the request and consume message content if enclosed. The consumer 053 * can optionally parse or transform the message content into a structured 054 * object which is then passed onto 055 * the {@link #handle(Object, HttpAsyncExchange, HttpContext)} 056 * method for further processing. 057 * 058 * @param request the entity enclosing request. 059 * @param context the execution context. 060 * @return request consumer. 061 * @throws IOException in case of an I/O error. 062 * @throws HttpException in case of HTTP protocol violation or a processing 063 * problem. 064 */ 065 HttpAsyncRequestConsumer<T> processRequest( 066 HttpRequest request, 067 HttpContext context) throws HttpException, IOException; 068 069 /** 070 * Triggered to complete request processing and to initiate the process of 071 * generating a response. This method does not have to submit a response 072 * immediately. It can defer transmission of an HTTP response back to 073 * the client without blocking the I/O thread by delegating the process 074 * of request handling to another service or a worker thread. HTTP response 075 * can be submitted as a later a later point of time using 076 * {@link HttpAsyncExchange} once response content becomes available. 077 * 078 * @param data request data returned by the request consumer. 079 * @param httpExchange HTTP exchange. 080 * @param context HTTP execution context. 081 * @throws IOException in case of an I/O error. 082 * @throws HttpException in case of HTTP protocol violation or a processing 083 * problem. 084 */ 085 void handle( 086 T data, 087 HttpAsyncExchange httpExchange, 088 HttpContext context) throws HttpException, IOException; 089 090}