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 */
027
028package org.apache.http.impl.client;
029
030import java.util.Locale;
031import java.util.Map;
032import java.util.concurrent.ConcurrentHashMap;
033
034import org.apache.http.HttpRequest;
035import org.apache.http.annotation.Contract;
036import org.apache.http.annotation.ThreadingBehavior;
037
038/**
039 * {@link org.apache.http.client.HttpRequestRetryHandler} which assumes
040 * that all requested HTTP methods which should be idempotent according
041 * to RFC-2616 are in fact idempotent and can be retried.
042 * <p>
043 * According to RFC-2616 section 9.1.2 the idempotent HTTP methods are:
044 * GET, HEAD, PUT, DELETE, OPTIONS, and TRACE
045 * </p>
046 *
047 * @since 4.2
048 */
049@Contract(threading = ThreadingBehavior.IMMUTABLE)
050public class StandardHttpRequestRetryHandler extends DefaultHttpRequestRetryHandler {
051
052    private final Map<String, Boolean> idempotentMethods;
053
054    /**
055     * Default constructor
056     */
057    public StandardHttpRequestRetryHandler(final int retryCount, final boolean requestSentRetryEnabled) {
058        super(retryCount, requestSentRetryEnabled);
059        this.idempotentMethods = new ConcurrentHashMap<String, Boolean>();
060        this.idempotentMethods.put("GET", Boolean.TRUE);
061        this.idempotentMethods.put("HEAD", Boolean.TRUE);
062        this.idempotentMethods.put("PUT", Boolean.TRUE);
063        this.idempotentMethods.put("DELETE", Boolean.TRUE);
064        this.idempotentMethods.put("OPTIONS", Boolean.TRUE);
065        this.idempotentMethods.put("TRACE", Boolean.TRUE);
066    }
067
068    /**
069     * Default constructor
070     */
071    public StandardHttpRequestRetryHandler() {
072        this(3, false);
073    }
074
075    @Override
076    protected boolean handleAsIdempotent(final HttpRequest request) {
077        final String method = request.getRequestLine().getMethod().toUpperCase(Locale.ROOT);
078        final Boolean b = this.idempotentMethods.get(method);
079        return b != null && b.booleanValue();
080    }
081
082}