JavaTM 2 Platform
Std. Ed. v1.4.1

javax.swing.event
Class SwingPropertyChangeSupport

java.lang.Object
  |
  +--java.beans.PropertyChangeSupport
        |
        +--javax.swing.event.SwingPropertyChangeSupport
All Implemented Interfaces:
Serializable

public final class SwingPropertyChangeSupport
extends PropertyChangeSupport

This subclass of java.beans.PropertyChangeSupport is identical in functionality -- it sacrifices thread-safety (not a Swing concern) for reduce memory consumption, which helps performance (both big Swing concerns). Most of the overridden methods are only necessary because all of PropertyChangeSupport's instance data is private, without accessor methods.


Constructor Summary
SwingPropertyChangeSupport(Object sourceBean)
          Constructs a SwingPropertyChangeSupport object.
 
Method Summary
 void addPropertyChangeListener(PropertyChangeListener listener)
          Add a PropertyChangeListener to the listener list.
 void addPropertyChangeListener(String propertyName, PropertyChangeListener listener)
          Add a PropertyChangeListener for a specific property.
 void firePropertyChange(PropertyChangeEvent evt)
          Fire an existing PropertyChangeEvent to any registered listeners.
 void firePropertyChange(String propertyName, Object oldValue, Object newValue)
          Report a bound property update to any registered listeners.
 PropertyChangeListener[] getPropertyChangeListeners()
          Returns an array of all the listeners that were added to the SwingPropertyChangeSupport object with addPropertyChangeListener().
 PropertyChangeListener[] getPropertyChangeListeners(String propertyName)
          Returns an array of all the listeners which have been associated with the named property.
 boolean hasListeners(String propertyName)
          Check if there are any listeners for a specific property.
 void removePropertyChangeListener(PropertyChangeListener listener)
          Remove a PropertyChangeListener from the listener list.
 void removePropertyChangeListener(String propertyName, PropertyChangeListener listener)
          Remove a PropertyChangeListener for a specific property.
 
Methods inherited from class java.beans.PropertyChangeSupport
firePropertyChange, firePropertyChange
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SwingPropertyChangeSupport

public SwingPropertyChangeSupport(Object sourceBean)
Constructs a SwingPropertyChangeSupport object.

Parameters:
sourceBean - The bean to be given as the source for any events.
Method Detail

addPropertyChangeListener

public void addPropertyChangeListener(PropertyChangeListener listener)
Add a PropertyChangeListener to the listener list. The listener is registered for all properties.

Overrides:
addPropertyChangeListener in class PropertyChangeSupport
Parameters:
listener - The PropertyChangeListener to be added

removePropertyChangeListener

public void removePropertyChangeListener(PropertyChangeListener listener)
Remove a PropertyChangeListener from the listener list. This removes a PropertyChangeListener that was registered for all properties.

Overrides:
removePropertyChangeListener in class PropertyChangeSupport
Parameters:
listener - The PropertyChangeListener to be removed

getPropertyChangeListeners

public PropertyChangeListener[] getPropertyChangeListeners()
Returns an array of all the listeners that were added to the SwingPropertyChangeSupport object with addPropertyChangeListener().

If some listeners have been added with a named property, then the returned array will be a mixture of PropertyChangeListeners and PropertyChangeListenerProxys. If the calling method is interested in distinguishing the listeners then it must test each element to see if it's a PropertyChangeListenerProxy perform the cast and examine the parameter.

 PropertyChangeListener[] listeners = support.getPropertyChangeListeners();
 for (int i = 0; i < listeners.length; i++) {
	 if (listeners[i] instanceof PropertyChangeListenerProxy) {
     PropertyChangeListenerProxy proxy = 
                    (PropertyChangeListenerProxy)listeners[i];
     if (proxy.getPropertyName().equals("foo")) {
       // proxy is a PropertyChangeListener which was associated
       // with the property named "foo"
     }
   }
 }

Overrides:
getPropertyChangeListeners in class PropertyChangeSupport
Returns:
all of the PropertyChangeListeners added or an empty array if no listeners have been added
Since:
1.4
See Also:
PropertyChangeListenerProxy, PropertyChangeSupport.getPropertyChangeListeners()

addPropertyChangeListener

public void addPropertyChangeListener(String propertyName,
                                      PropertyChangeListener listener)
Add a PropertyChangeListener for a specific property. The listener will be invoked only when a call on firePropertyChange names that specific property.

Overrides:
addPropertyChangeListener in class PropertyChangeSupport
Parameters:
propertyName - The name of the property to listen on.
listener - The PropertyChangeListener to be added

removePropertyChangeListener

public void removePropertyChangeListener(String propertyName,
                                         PropertyChangeListener listener)
Remove a PropertyChangeListener for a specific property.

Overrides:
removePropertyChangeListener in class PropertyChangeSupport
Parameters:
propertyName - The name of the property that was listened on.
listener - The PropertyChangeListener to be removed

getPropertyChangeListeners

public PropertyChangeListener[] getPropertyChangeListeners(String propertyName)
Returns an array of all the listeners which have been associated with the named property.

Overrides:
getPropertyChangeListeners in class PropertyChangeSupport
Returns:
all of the PropertyChangeListeners associated with the named property or an empty array if no listeners have been added

firePropertyChange

public void firePropertyChange(String propertyName,
                               Object oldValue,
                               Object newValue)
Report a bound property update to any registered listeners. No event is fired if old and new are equal and non-null.

Overrides:
firePropertyChange in class PropertyChangeSupport
Parameters:
propertyName - The programmatic name of the property that was changed.
oldValue - The old value of the property.
newValue - The new value of the property.

firePropertyChange

public void firePropertyChange(PropertyChangeEvent evt)
Fire an existing PropertyChangeEvent to any registered listeners. No event is fired if the given event's old and new values are equal and non-null.

Overrides:
firePropertyChange in class PropertyChangeSupport
Parameters:
evt - The PropertyChangeEvent object.

hasListeners

public boolean hasListeners(String propertyName)
Check if there are any listeners for a specific property.

Overrides:
hasListeners in class PropertyChangeSupport
Parameters:
propertyName - the property name.
Returns:
true if there are ore or more listeners for the given property

JavaTM 2 Platform
Std. Ed. v1.4.1

Submit a bug or feature
For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2002 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.