// Fire an event to all listeners registered with this node.
private void fireEvent(String propName, Object oldVal, Object newVal) {
if (eventManager != null) {
Object eventSource = eventManager.getPropertyChangeEventSource();
PropertyChangeEventJAI evt =
new PropertyChangeEventJAI(eventSource,
propName, oldVal, newVal);
eventManager.firePropertyChange(evt);
}
}