Index: httpclient/src/main/java/org/apache/http/impl/client/DefaultIdempotentHttpRequestRetryHandler.java =================================================================== --- httpclient/src/main/java/org/apache/http/impl/client/DefaultIdempotentHttpRequestRetryHandler.java (revision 0) +++ httpclient/src/main/java/org/apache/http/impl/client/DefaultIdempotentHttpRequestRetryHandler.java (revision 0) @@ -0,0 +1,136 @@ +/* + * ==================================================================== + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + * ==================================================================== + * + * This software consists of voluntary contributions made by many + * individuals on behalf of the Apache Software Foundation. For more + * information on the Apache Software Foundation, please see + * . + * + */ + +package org.apache.http.impl.client; + +import java.io.IOException; +import java.io.InterruptedIOException; +import java.net.ConnectException; +import java.net.UnknownHostException; + +import javax.net.ssl.SSLException; + +import org.apache.http.annotation.Immutable; +import org.apache.http.client.HttpRequestRetryHandler; +import org.apache.http.client.methods.HttpPost; +import org.apache.http.protocol.HttpContext; +import org.apache.http.protocol.ExecutionContext; + +/** + * A {@link HttpRequestRetryHandler} which assumes that all requested + * HTTP methods which should be idempotent according to RFC-2616 are + * in fact idempotent and can be retried. + * + * According to RFC-2616 section 9.1.2 the idempotent HTTP methods are: + * GET, HEAD, PUT, DELETE, OPTIONS, and TRACE + * + * @since 4.1 + */ +@Immutable +public class DefaultIdempotentHttpRequestRetryHandler implements HttpRequestRetryHandler { + + /** the number of times a method will be retried */ + private final int retryCount; + + /** + * Default constructor + */ + public DefaultIdempotentHttpRequestRetryHandler(int retryCount) { + super(); + this.retryCount = retryCount; + } + + /** + * Default constructor + */ + public DefaultIdempotentHttpRequestRetryHandler() { + this(3); + } + /** + * Used retryCount to determine + * if the given method should be retried. + */ + public boolean retryRequest( + final IOException exception, + int executionCount, + final HttpContext context) { + if (exception == null) { + throw new IllegalArgumentException("Exception parameter may not be null"); + } + if (context == null) { + throw new IllegalArgumentException("HTTP context may not be null"); + } + if (executionCount > this.retryCount) { + // Do not retry if over max retry count + return false; + } + if (exception instanceof InterruptedIOException) { + // Timeout + return false; + } + if (exception instanceof UnknownHostException) { + // Unknown host + return false; + } + if (exception instanceof ConnectException) { + // Connection refused + return false; + } + if (exception instanceof SSLException) { + // SSL handshake exception + return false; + } + + Boolean b = (Boolean)context.getAttribute(ExecutionContext.HTTP_REQ_SENT); + boolean sent = (b != null && b.booleanValue()); + if (!sent) { + // Retry if the request has not been sent fully + return true; + } + + // From the current list of supported HTTP methods: + // GET, HEAD, POST, PUT, DELETE, OPTIONS, and TRACE + // RFC-2616 section 9.1.2 declares the following should be idempotent: + // GET, HEAD, PUT, DELETE, OPTIONS, and TRACE + Object requestObj = context.getAttribute(ExecutionContext.HTTP_REQUEST); + boolean idempotent = !(requestObj instanceof HttpPost); + if (idempotent) { + // Retry if the request is considered idempotent + return true; + } + + // otherwise do not retry + return false; + } + + /** + * @return the maximum number of times a method will be retried + */ + public int getRetryCount() { + return retryCount; + } +}