content: /* Alloy Analyzer 4 -- Copyright (c) 2006-2009, Felix Chang
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files
   * (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify,
   * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
   * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
   * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   */
  
  package edu.mit.csail.sdg.alloy4;
  
  import java.util.ArrayList;
  
  import edu.mit.csail.sdg.alloy4.Listener.Event;
  
  /** This stores a list of listeners. */
  
  public final class Listeners {
  
      /** The actual list of listeners. */
      private final ArrayList<Listener> listeners = new ArrayList<Listener>();
  
      /** Construct a empty list of listeners. */
      public Listeners() {}
  
      /**
       * Add a listener to this group of listeners (if not already in the list)
       */
      public void add(Listener listener) {
          for (Listener x : listeners)
              if (x == listener)
                  return;
          listeners.add(listener);
      }
  
      /**
       * Send the following zero-argument event to every listener.
       */
      public void fire(Object sender, Event event) {
          for (Listener x : listeners)
              x.do_action(sender, event);
      }
  
      /**
       * Send the following one-argument event to every listener.
       */
      public void fire(Object sender, Event event, Object arg) {
          for (Listener x : listeners)
              x.do_action(sender, event, arg);
      }
  }
  