Package org.eclipse.core.commands.common

Class EventManager

java.lang.Object

org.eclipse.core.commands.common.EventManager

Direct Known Subclasses:

AbstractAction, AbstractHandler, BaseLabelProvider, ColorSelector, FrameList, HandleObject, HandleObjectManager, IntroPart, PreferenceStore, PropertySheetEntry, ResourceRegistry, ResourceTreeAndListGroup, ScopedPreferenceStore, State, SubActionBars, WorkbenchPart

public abstract class EventManager
extends Object

A manager to which listeners can be attached. This handles the management of a list of listeners -- optimizing memory and performance. All the methods on this class are guaranteed to be thread-safe.

Clients may extend.

Warning: Do not use this class! Use ListenerList directly. See bug 486067.

Since:

3.2

Constructor Summary

Constructors

Constructor	Description
EventManager()

Method Summary

Modifier and Type	Method	Description
protected void	addListenerObject(Object listener)	Adds a listener to this manager that will be notified when this manager's state changes.
protected void	clearListeners()	Clears all of the listeners from the listener list.
protected Object[]	getListeners()	Returns an array containing all the listeners attached to this event manager.
protected boolean	isListenerAttached()	Whether one or more listeners are attached to the manager.
protected void	removeListenerObject(Object listener)	Removes a listener from this manager.

Methods inherited from class java.lang.Object

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

Constructor Detail

EventManager

public EventManager()

Method Detail

addListenerObject

protected final void addListenerObject(Object listener)

Adds a listener to this manager that will be notified when this manager's state changes. This method has no effect if the same listener is already registered.

Parameters:

listener - The listener to be added; must not be null.

clearListeners

protected final void clearListeners()

Clears all of the listeners from the listener list.

getListeners

protected final Object[] getListeners()

Returns an array containing all the listeners attached to this event manager. The resulting array is unaffected by subsequent adds or removes. If there are no listeners registered, the result is an empty array. Use this method when notifying listeners, so that any modifications to the listener list during the notification will have no effect on the notification itself.

Note: Callers of this method must not modify the returned array.

Returns:

The listeners currently attached; may be empty, but never null

isListenerAttached

protected final boolean isListenerAttached()

Whether one or more listeners are attached to the manager.

Returns:

true if listeners are attached to the manager; false otherwise.

removeListenerObject

protected final void removeListenerObject(Object listener)

Removes a listener from this manager. Has no effect if the same listener was not already registered.

Parameters:

listener - The listener to be removed; must not be null.