package com.microchip.mplab.ipelib.common;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;

public class ChangeEventHandler {
   private PropertyChangeSupport pcs = null;
   private static ChangeEventHandler inst;
   private ChangeEventHandler.DeviceChangeListener devChangeListener = new ChangeEventHandler.DeviceChangeListener();

   private ChangeEventHandler() {
      this.pcs = new PropertyChangeSupport(this);
   }

   public static void addPropertyChangeListener(PropertyChangeListener listener) {
      getSingleton().pcs.addPropertyChangeListener(listener);
   }

   public static void removePropertyChangeListener(PropertyChangeListener listener) {
      getSingleton().pcs.removePropertyChangeListener(listener);
   }

   public static ChangeEventHandler getSingleton() {
      if (inst != null) {
         return inst;
      } else {
         inst = new ChangeEventHandler();
         return inst;
      }
   }

   public ChangeEventHandler.DeviceChangeListener getDeviceChangeListener() {
      return this.devChangeListener;
   }

   public class DeviceChangeListener {
      public void stateChanged(PropertyChangeEvent event) {
         if (event != null) {
            ChangeEventHandler.this.pcs.firePropertyChange(event);
         }
      }
   }
}