title: Java listener must inherit from java.util.EventListener - why?
body: <p>In the javadoc it says that EventListener is </p>
  
  <blockquote>
    <p>"A tagging interface that all event listener interfaces must extend."</p>
  </blockquote>
  
  <p>Why is that? What's the significance of making a custom listener implement EventListner? Is there any special handling for EventListner somewhere?</p>