The Tor Browser / file revision

 /*

  * ====================================================================

  * 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

  * <http://www.apache.org/>.

  *

  */

 package ch.boye.httpclientandroidlib.impl.client;

 import java.io.IOException;

 import java.io.InterruptedIOException;

 import java.net.ConnectException;

 import java.net.UnknownHostException;

 import javax.net.ssl.SSLException;

 import ch.boye.httpclientandroidlib.annotation.Immutable;

 import ch.boye.httpclientandroidlib.HttpEntityEnclosingRequest;

 import ch.boye.httpclientandroidlib.HttpRequest;

 import ch.boye.httpclientandroidlib.client.HttpRequestRetryHandler;

 import ch.boye.httpclientandroidlib.protocol.HttpContext;

 import ch.boye.httpclientandroidlib.protocol.ExecutionContext;

 /**

  * The default {@link HttpRequestRetryHandler} used by request executors.

  *

  *

  * @since 4.0

  */

 @Immutable

 public class DefaultHttpRequestRetryHandler implements HttpRequestRetryHandler {

     /** the number of times a method will be retried */

     private final int retryCount;

     /** Whether or not methods that have successfully sent their request will be retried */

     private final boolean requestSentRetryEnabled;

     /**

      * Default constructor

      */

     public DefaultHttpRequestRetryHandler(int retryCount, boolean requestSentRetryEnabled) {

         super();

         this.retryCount = retryCount;

         this.requestSentRetryEnabled = requestSentRetryEnabled;

     }

     /**

      * Default constructor

      */

     public DefaultHttpRequestRetryHandler() {

         this(3, false);

     }

     /**

      * Used <code>retryCount</code> and <code>requestSentRetryEnabled</code> 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;

         }

         HttpRequest request = (HttpRequest)

             context.getAttribute(ExecutionContext.HTTP_REQUEST);

         if (handleAsIdempotent(request)) {

             // Retry if the request is considered idempotent

             return true;

         }

         Boolean b = (Boolean)

             context.getAttribute(ExecutionContext.HTTP_REQ_SENT);

         boolean sent = (b != null && b.booleanValue());

         if (!sent || this.requestSentRetryEnabled) {

             // Retry if the request has not been sent fully or

             // if it's OK to retry methods that have been sent

             return true;

         }

         // otherwise do not retry

         return false;

     }

     /**

      * @return <code>true</code> if this handler will retry methods that have

      * successfully sent their request, <code>false</code> otherwise

      */

     public boolean isRequestSentRetryEnabled() {

         return requestSentRetryEnabled;

     }

     /**

      * @return the maximum number of times a method will be retried

      */

     public int getRetryCount() {

         return retryCount;

     }

     private boolean handleAsIdempotent(final HttpRequest request) {

         return !(request instanceof HttpEntityEnclosingRequest);

     }

 }