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.impl.client;
028
029import java.net.ConnectException;
030import java.net.SocketTimeoutException;
031
032import org.apache.http.HttpResponse;
033import org.apache.http.HttpStatus;
034import org.apache.http.client.ConnectionBackoffStrategy;
035
036/**
037 * This {@link ConnectionBackoffStrategy} backs off either for a raw
038 * network socket or connection timeout or if the server explicitly
039 * sends a 503 (Service Unavailable) response.
040 *
041 * @since 4.2
042 */
043public class DefaultBackoffStrategy implements ConnectionBackoffStrategy {
044
045    @Override
046    public boolean shouldBackoff(final Throwable t) {
047        return (t instanceof SocketTimeoutException
048                || t instanceof ConnectException);
049    }
050
051    @Override
052    public boolean shouldBackoff(final HttpResponse resp) {
053        return (resp.getStatusLine().getStatusCode() == HttpStatus.SC_SERVICE_UNAVAILABLE);
054    }
055
056}