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.hc.client5.http.classic; 29 30 import java.io.IOException; 31 32 import org.apache.hc.core5.annotation.Contract; 33 import org.apache.hc.core5.annotation.ThreadingBehavior; 34 import org.apache.hc.core5.http.ClassicHttpRequest; 35 import org.apache.hc.core5.http.ClassicHttpResponse; 36 import org.apache.hc.core5.http.HttpException; 37 38 /** 39 * Abstract request execution handler in a classic client side request execution chain. 40 * Handlers can either be a decorator around another element that implements a cross 41 * cutting aspect or a self-contained executor capable of producing a response 42 * for the given request. 43 * <p> 44 * Important: please note it is required for decorators that implement post execution aspects 45 * or response post-processing of any sort to release resources associated with the response 46 * by calling {@link ClassicHttpResponse#close()} methods in case of an I/O, protocol or 47 * runtime exception, or in case the response is not propagated to the caller. 48 * </p> 49 * 50 * @since 4.3 51 */ 52 @Contract(threading = ThreadingBehavior.STATELESS) 53 public interface ExecChainHandler { 54 55 /** 56 * Executes the actual HTTP request. The handler can choose to return 57 * a response message or delegate request execution to the next element 58 * in the execution chain. 59 * 60 * @param request the actual request. 61 * @param scope the execution scope . 62 * @param chain the next element in the request execution chain. 63 */ 64 ClassicHttpResponse execute( 65 ClassicHttpRequest request, 66 ExecChain.Scope scope, 67 ExecChain chain) throws IOException, HttpException; 68 69 }