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.impl.classic; 29 30 import java.io.IOException; 31 32 import org.apache.hc.client5.http.HttpResponseException; 33 import org.apache.hc.core5.annotation.Contract; 34 import org.apache.hc.core5.annotation.ThreadingBehavior; 35 import org.apache.hc.core5.http.ClassicHttpResponse; 36 import org.apache.hc.core5.http.HttpEntity; 37 import org.apache.hc.core5.http.HttpStatus; 38 import org.apache.hc.core5.http.io.HttpClientResponseHandler; 39 import org.apache.hc.core5.http.io.entity.EntityUtils; 40 41 /** 42 * A generic {@link HttpClientResponseHandler} that works with the response entity 43 * for successful (2xx) responses. If the response code was >= 300, the response 44 * body is consumed and an {@link HttpResponseException} is thrown. 45 * <p> 46 * If this is used with 47 * {@link org.apache.hc.client5.http.classic.HttpClient#execute( 48 * org.apache.hc.core5.http.ClassicHttpRequest, HttpClientResponseHandler)}, 49 * HttpClient may handle redirects (3xx responses) internally. 50 * </p> 51 * 52 * @since 4.4 53 */ 54 @Contract(threading = ThreadingBehavior.STATELESS) 55 public abstract class AbstractHttpClientResponseHandler<T> implements HttpClientResponseHandler<T> { 56 57 /** 58 * Read the entity from the response body and pass it to the entity handler 59 * method if the response was successful (a 2xx status code). If no response 60 * body exists, this returns null. If the response was unsuccessful (>= 300 61 * status code), throws an {@link HttpResponseException}. 62 */ 63 @Override 64 public T handleResponse(final ClassicHttpResponse response) throws IOException { 65 final HttpEntity entity = response.getEntity(); 66 if (response.getCode() >= HttpStatus.SC_REDIRECTION) { 67 EntityUtils.consume(entity); 68 throw new HttpResponseException(response.getCode(), response.getReasonPhrase()); 69 } 70 return entity == null ? null : handleEntity(entity); 71 } 72 73 /** 74 * Handle the response entity and transform it into the actual response 75 * object. 76 */ 77 public abstract T handleEntity(HttpEntity entity) throws IOException; 78 79 }