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 */ 027package org.apache.http.client; 028 029import org.apache.http.HttpResponse; 030 031/** 032 * When managing a dynamic number of connections for a given route, this 033 * strategy assesses whether a given request execution outcome should 034 * result in a backoff signal or not, based on either examining the 035 * {@code Throwable} that resulted or by examining the resulting 036 * response (e.g. for its status code). 037 * 038 * @since 4.2 039 * 040 */ 041public interface ConnectionBackoffStrategy { 042 043 /** 044 * Determines whether seeing the given {@code Throwable} as 045 * a result of request execution should result in a backoff 046 * signal. 047 * @param t the {@code Throwable} that happened 048 * @return {@code true} if a backoff signal should be 049 * given 050 */ 051 boolean shouldBackoff(Throwable t); 052 053 /** 054 * Determines whether receiving the given {@link HttpResponse} as 055 * a result of request execution should result in a backoff 056 * signal. Implementations MUST restrict themselves to examining 057 * the response header and MUST NOT consume any of the response 058 * body, if any. 059 * @param resp the {@code HttpResponse} that was received 060 * @return {@code true} if a backoff signal should be 061 * given 062 */ 063 boolean shouldBackoff(HttpResponse resp); 064}