Package org.eclipse.core.commands.common

Class EventManager

java.lang.Object
org.eclipse.core.commands.common.EventManager
Direct Known Subclasses:
AbstractAction, AbstractHandler, AbstractWorkingSetManager, BaseLabelProvider, ColorSelector, FrameList, HandleObject, HandleObjectManager, IntroPart, PageListenerList, PerspectiveListenerList, PreferenceStore, PropertySheetEntry, ResourceRegistry, ResourceTreeAndListGroup, ScopedPreferenceStore, State, SubActionBars, Workbench, 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 Details

    • EventManager

      public EventManager()

  • Method Details

    • 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.