Java in a Nutshell, 5th Edition

Name

TooManyListenersException

Synopsis

Signals that an AWT component, JavaBeans component, or Swing component can have only one EventListener object registered for some specific type of event. That is, it signals that a particular event is a unicast event rather than a multicast event. This exception type serves a formal purpose in the Java event model; its presence in the throws clause of an EventListener registration method (even if the method never actually throws the exception) signals that an event is a unicast event.

Figure 16-62. java.util.TooManyListenersException

public class TooManyListenersException extends Exception {
// Public Constructors
     public TooManyListenersException( );  
     public TooManyListenersException(String s);  
}