content: /*
   * Copyright (c) 2013. wyouflf (wyouflf@gmail.com)
   *
   * Licensed 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.
   */
  
  package com.lidroid.xutils.http.client;
  
  import android.os.SystemClock;
  import com.lidroid.xutils.util.LogUtils;
  import org.apache.http.NoHttpResponseException;
  import org.apache.http.client.HttpRequestRetryHandler;
  import org.apache.http.client.methods.HttpRequestBase;
  import org.apache.http.impl.client.RequestWrapper;
  import org.apache.http.protocol.ExecutionContext;
  import org.apache.http.protocol.HttpContext;
  
  import javax.net.ssl.SSLHandshakeException;
  import java.io.IOException;
  import java.io.InterruptedIOException;
  import java.net.SocketException;
  import java.net.UnknownHostException;
  import java.util.HashSet;
  
  public class RetryHandler implements HttpRequestRetryHandler {
  
      private static final int RETRY_SLEEP_INTERVAL = 500;
  
      private static HashSet<Class<?>> exceptionWhiteList = new HashSet<Class<?>>();
  
      private static HashSet<Class<?>> exceptionBlackList = new HashSet<Class<?>>();
  
      static {
          exceptionWhiteList.add(NoHttpResponseException.class);
          exceptionWhiteList.add(UnknownHostException.class);
          exceptionWhiteList.add(SocketException.class);
  
          exceptionBlackList.add(InterruptedIOException.class);
          exceptionBlackList.add(SSLHandshakeException.class);
      }
  
      private final int maxRetries;
  
      public RetryHandler(int maxRetries) {
          this.maxRetries = maxRetries;
      }
  
      @Override
      public boolean retryRequest(IOException exception, int retriedTimes, HttpContext context) {
          boolean retry = true;
  
          if (exception == null || context == null) {
              return false;
          }
  
          Object isReqSent = context.getAttribute(ExecutionContext.HTTP_REQ_SENT);
          boolean sent = isReqSent == null ? false : (Boolean) isReqSent;
  
          if (retriedTimes > maxRetries) {
              retry = false;
          } else if (exceptionBlackList.contains(exception.getClass())) {
              retry = false;
          } else if (exceptionWhiteList.contains(exception.getClass())) {
              retry = true;
          } else if (!sent) {
              retry = true;
          }
  
          if (retry) {
              try {
                  Object currRequest = context.getAttribute(ExecutionContext.HTTP_REQUEST);
                  if (currRequest != null) {
                      if (currRequest instanceof HttpRequestBase) {
                          HttpRequestBase requestBase = (HttpRequestBase) currRequest;
                          retry = "GET".equals(requestBase.getMethod());
                      } else if (currRequest instanceof RequestWrapper) {
                          RequestWrapper requestWrapper = (RequestWrapper) currRequest;
                          retry = "GET".equals(requestWrapper.getMethod());
                      }
                  } else {
                      retry = false;
                      LogUtils.e("retry error, curr request is null");
                  }
              } catch (Throwable e) {
                  retry = false;
                  LogUtils.e("retry error", e);
              }
          }
  
          if (retry) {
              SystemClock.sleep(RETRY_SLEEP_INTERVAL); // sleep a while and retry http request again.
          }
  
          return retry;
      }
  
  }