/*
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   package nl.tudelft.goal.ut2004.visualizer.services;
   
   import java.util.ArrayList;
   import java.util.HashSet;
   import java.util.List;
  import java.util.Set;
  
  /**
   * This is a selection set for one environment(server, timeline).
   * <p>
   * It is possible to listen for changes in selection and change selected entities.
   * Nothing more for now.
   *
   * @author Honza
   */
  public class AgentSelection<E> {
      private E selected = null;
      private Set<ISelectionListener<E>> listeners = new HashSet<ISelectionListener<E>>();
  
      public synchronized void changeSelected(E newSelection) {
          E oldSelected = selected;
          selected = newSelection;
  
          fireSelectionPropertyChange(oldSelected, newSelection);
      }
      
      public synchronized void addSelectionListener(ISelectionListener<E> listener) {
          this.listeners.add(listener);
      }
      
      public synchronized void removeSelectionListener(ISelectionListener<E> listener) {
          this.listeners.remove(listener);
      }
  
      private synchronized void fireSelectionPropertyChange(E oldSelection, E newSelection) {
          List<ISelectionListener<E>> listenersArray = new ArrayList<ISelectionListener<E>>(listeners);
  
          for (ISelectionListener<E> listener : listenersArray) {
              listener.selectionChanged(oldSelection, newSelection);
          }
      }
  
  }