lava.util
Class ListenerRegistry

java.lang.Object
  |
  +--lava.util.ListenerRegistry

public class ListenerRegistry

extends java.lang.Object

Listener registry.

Details: This class maintains a mutable registry of listeners who would like to receive messages for certain types of events. This is a support class for use in classes that support listeners.

Since:

1999.08.13

Author:

Sharky

Constructor Summary

ListenerRegistry()

Method Summary

java.util.Enumeration	getListeners() Enumerates registered listeners.
void	registerListener(java.lang.Object listener) Registers a listener.
void	unregisterListener(java.lang.Object listener) Unregisters a listener.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ListenerRegistry

public ListenerRegistry()

Method Detail

registerListener

public void registerListener(java.lang.Object listener)

Registers a listener.

Details: This method registers the given listener to receive messsages from the owner of this registry. A listener cannot be added twice. No action is taken if the listener is already registered.

Parameters:

listener - the listener to register

Since:

1988.10.22

unregisterListener

public void unregisterListener(java.lang.Object listener)

Unregisters a listener.

Details: This method unregisters the given listener so that it no longer receives messages from the registry owner. No action is taken if the listener is not registered.

Listeners should unregister themselves when they no longer need to receive messages.

Parameters:

listener - the listener to unregister

Since:

1988.10.22

getListeners

public java.util.Enumeration getListeners()

Enumerates registered listeners.

Details: This method returns an Enumeration of all the registered listeners. Since the returned Enumeration exists independently of the internally stored listener list, new elements may be added to this registery and old elements may be removed from this registry while the Enumeration is being processed.

Returns:

the Enumeration