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 package org.apache.hc.client5.http.async; 28 29 import java.io.IOException; 30 31 import org.apache.hc.client5.http.impl.ChainElement; 32 import org.apache.hc.client5.http.impl.async.AsyncHttpRequestRetryExec; 33 import org.apache.hc.client5.http.impl.async.HttpAsyncClientBuilder; 34 import org.apache.hc.core5.annotation.Contract; 35 import org.apache.hc.core5.annotation.ThreadingBehavior; 36 import org.apache.hc.core5.http.HttpException; 37 import org.apache.hc.core5.http.HttpRequest; 38 import org.apache.hc.core5.http.nio.AsyncEntityProducer; 39 40 /** 41 * Abstract request execution handler in an asynchronous client side request execution 42 * chain. Handlers can either be a decorator around another element that implements 43 * a cross cutting aspect or a self-contained executor capable of producing a response 44 * for the given request. 45 * <p> 46 * For information regarding the handler chain behaviour in case of a request re-execution, 47 * please refer to the {@link AsyncHttpRequestRetryExec} javadoc. 48 * </p> 49 * <p> 50 * Well known request execution handlers could be referred to by name using one of the 51 * {@link ChainElement} enum values. 52 * </p> 53 * @since 5.0 54 * @see ChainElement 55 * @see HttpAsyncClientBuilder#addExecInterceptorFirst(String, AsyncExecChainHandler) 56 * @see HttpAsyncClientBuilder#addExecInterceptorBefore(String, String, AsyncExecChainHandler) 57 * @see HttpAsyncClientBuilder#addExecInterceptorAfter(String, String, AsyncExecChainHandler) 58 * @see HttpAsyncClientBuilder#addExecInterceptorLast(String, AsyncExecChainHandler) 59 */ 60 @Contract(threading = ThreadingBehavior.STATELESS) 61 public interface AsyncExecChainHandler { 62 63 /** 64 * Executes the actual HTTP request. The handler can choose to return 65 * a response message immediately inside the call or asynchronously 66 * at some later point or delegate request execution to the next 67 * element in the execution chain. 68 * 69 * @param request the actual request. 70 * @param entityProducer the request entity producer or {@code null} if the request 71 * does not enclose an entity. 72 * @param scope the execution scope . 73 * @param chain the next element in the request execution chain. 74 * @param asyncExecCallback the execution callback. 75 */ 76 void execute( 77 HttpRequest request, 78 AsyncEntityProducer entityProducer, 79 AsyncExecChain.Scope scope, 80 AsyncExecChain chain, 81 AsyncExecCallback asyncExecCallback) throws HttpException, IOException; 82 83 }