content: /*
   * Copyright (C) 2006 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 android.os;
  
  import android.annotation.UnsupportedAppUsage;
  import android.os.Handler;         
  
  import java.util.ArrayList;
  
  /** @hide */
  public class RegistrantList
  {
      ArrayList   registrants = new ArrayList();      // of Registrant
  
      @UnsupportedAppUsage
      public synchronized void
      add(Handler h, int what, Object obj)
      {
          add(new Registrant(h, what, obj));
      }
  
      @UnsupportedAppUsage
      public synchronized void
      addUnique(Handler h, int what, Object obj)
      {
          // if the handler is already in the registrant list, remove it
          remove(h);
          add(new Registrant(h, what, obj));        
      }
      
      @UnsupportedAppUsage
      public synchronized void
      add(Registrant r)
      {
          removeCleared();
          registrants.add(r);
      }
  
      @UnsupportedAppUsage
      public synchronized void
      removeCleared()
      {
          for (int i = registrants.size() - 1; i >= 0 ; i--) {
              Registrant  r = (Registrant) registrants.get(i);
              
              if (r.refH == null) {
                  registrants.remove(i);
              }
          }
      }
  
      @UnsupportedAppUsage
      public synchronized int
      size()
      {
          return registrants.size();
      }
  
      public synchronized Object
      get(int index)
      {
          return registrants.get(index);
      }
  
      private synchronized void
      internalNotifyRegistrants (Object result, Throwable exception)
      {
         for (int i = 0, s = registrants.size(); i < s ; i++) {
              Registrant  r = (Registrant) registrants.get(i);
              r.internalNotifyRegistrant(result, exception);
         }
      }
      
      @UnsupportedAppUsage
      public /*synchronized*/ void
      notifyRegistrants()
      {
          internalNotifyRegistrants(null, null);
      }
  
      public /*synchronized*/ void
      notifyException(Throwable exception)
      {
          internalNotifyRegistrants (null, exception);
      }
  
      @UnsupportedAppUsage
      public /*synchronized*/ void
      notifyResult(Object result)
      {
          internalNotifyRegistrants (result, null);
      }
  
      
      @UnsupportedAppUsage
      public /*synchronized*/ void
      notifyRegistrants(AsyncResult ar)
      {
          internalNotifyRegistrants(ar.result, ar.exception);
      }
      
      @UnsupportedAppUsage
      public synchronized void
      remove(Handler h)
      {
          for (int i = 0, s = registrants.size() ; i < s ; i++) {
              Registrant  r = (Registrant) registrants.get(i);
              Handler     rh;
  
              rh = r.getHandler();
  
              /* Clean up both the requested registrant and
               * any now-collected registrants
               */
              if (rh == null || rh == h) {
                  r.clear();
              }
          }
  
          removeCleared();
      }
  }
  