content: /*
   * Copyright (C) 2011 The Android Open Source Project
   *
   * 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.cjj.volley.toolbox;
  
  import com.cjj.volley.Cache;
  import com.cjj.volley.NetworkResponse;
  import com.cjj.volley.Request;
  import com.cjj.volley.Response;
  
  import android.os.Handler;
  import android.os.Looper;
  
  /**
   * A synthetic request used for clearing the cache.
   */
  public class ClearCacheRequest extends Request<Object> {
      private final Cache mCache;
      private final Runnable mCallback;
  
      /**
       * Creates a synthetic request for clearing the cache.
       * @param cache Cache to clear
       * @param callback Callback to make on the main thread once the cache is clear,
       * or null for none
       */
      public ClearCacheRequest(Cache cache, Runnable callback) {
          super(Method.GET, null, null);
          mCache = cache;
          mCallback = callback;
      }
  
      @Override
      public boolean isCanceled() {
          // This is a little bit of a hack, but hey, why not.
          mCache.clear();
          if (mCallback != null) {
              Handler handler = new Handler(Looper.getMainLooper());
              handler.postAtFrontOfQueue(mCallback);
          }
          return true;
      }
  
      @Override
      public Priority getPriority() {
          return Priority.IMMEDIATE;
      }
  
      @Override
      protected Response<Object> parseNetworkResponse(NetworkResponse response) {
          return null;
      }
  
      @Override
      protected void deliverResponse(Object response) {
      }
  }
  