L - the type of event listener that is supported by this proxy.public class EventListenerSupport<L>
extends java.lang.Object
implements java.io.Serializable
An EventListenerSupport object can be used to manage a list of event
listeners of a particular type. The class provides
addListener(Object) and removeListener(Object) methods
for registering listeners, as well as a fire() method for firing
events to the listeners.
To use this class, suppose you want to support ActionEvents. You would do:
public class MyActionEventSource
{
private EventListenerSupport<ActionListener> actionListeners =
EventListenerSupport.create(ActionListener.class);
public void someMethodThatFiresAction()
{
ActionEvent e = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "somethingCool");
actionListeners.fire().actionPerformed(e);
}
}
Serializing an EventListenerSupport instance will result in any
non-Serializable listeners being silently dropped.
| Modifier and Type | Class and Description |
|---|---|
protected class |
EventListenerSupport.ProxyInvocationHandler
An invocation handler used to dispatch the event(s) to all the listeners.
|
| Constructor and Description |
|---|
EventListenerSupport(java.lang.Class<L> listenerInterface)
Creates an EventListenerSupport object which supports the provided
listener interface.
|
EventListenerSupport(java.lang.Class<L> listenerInterface,
java.lang.ClassLoader classLoader)
Creates an EventListenerSupport object which supports the provided
listener interface using the specified class loader to create the JDK
dynamic proxy.
|
| Modifier and Type | Method and Description |
|---|---|
void |
addListener(L listener)
Registers an event listener.
|
void |
addListener(L listener,
boolean allowDuplicate)
Registers an event listener.
|
static <T> EventListenerSupport<T> |
create(java.lang.Class<T> listenerInterface)
Creates an EventListenerSupport object which supports the specified
listener type.
|
protected java.lang.reflect.InvocationHandler |
createInvocationHandler()
Create the
InvocationHandler responsible for broadcasting calls
to the managed listeners. |
L |
fire()
Returns a proxy object which can be used to call listener methods on all
of the registered event listeners.
|
L[] |
getListeners()
Get an array containing the currently registered listeners.
|
void |
removeListener(L listener)
Unregisters an event listener.
|
public EventListenerSupport(java.lang.Class<L> listenerInterface)
listenerInterface - the type of listener interface that will receive
events posted using this class.java.lang.NullPointerException - if listenerInterface is
null.java.lang.IllegalArgumentException - if listenerInterface is
not an interface.public EventListenerSupport(java.lang.Class<L> listenerInterface, java.lang.ClassLoader classLoader)
listenerInterface - the listener interface.classLoader - the class loader.java.lang.NullPointerException - if listenerInterface or
classLoader is null.java.lang.IllegalArgumentException - if listenerInterface is
not an interface.public static <T> EventListenerSupport<T> create(java.lang.Class<T> listenerInterface)
T - the type of the listener interfacelistenerInterface - the type of listener interface that will receive
events posted using this class.java.lang.NullPointerException - if listenerInterface is
null.java.lang.IllegalArgumentException - if listenerInterface is
not an interface.public L fire()
public void addListener(L listener)
listener - the event listener (may not be null).java.lang.NullPointerException - if listener is
null.public void addListener(L listener, boolean allowDuplicate)
allowDuplicate is false.listener - the event listener (may not be null).allowDuplicate - the flag for determining if duplicate listener
objects are allowed to be registered.java.lang.NullPointerException - if listener is null.public void removeListener(L listener)
listener - the event listener (may not be null).java.lang.NullPointerException - if listener is
null.public L[] getListeners()
EventListenerSupport instance.protected java.lang.reflect.InvocationHandler createInvocationHandler()
InvocationHandler responsible for broadcasting calls
to the managed listeners. Subclasses can override to provide custom behavior.