Event Handling In Java Part II - Explicit-Event Handling
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An alternate way to handle events is to sub class the components and override the method that receives and dispatches event. For example you can drive a class from Button class and override the processActionEvent() method. The default action of the processActionEvent() method is to dispatch the event to the event listeners.

Example1:

Class OKButton extends Button
{
       Public OKButton (String caption)
       {
           super(caption);
           //enable processing of action events
            enableEvents(AWTEvent.Action_Event_Mask);
         }

         Public void processActionEvent(ActionEvent e)
          {
               // process event, and call superclass method 
			   // as it calls actionPerformed() method
                  super.processActionEvent(action);
         }
}

A subclass can act as an event listener for itself as shown in the following code:

Class OKButton extends Button implements ActionListener
{
   Public OKButton(String caption)
   {
           super(caption);
           //add an action listener to the button
             addActionListener(this);
    }
    Public void actionPerformed(ActionEvent ae)
   {
         // code to process event
    }
}

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