code: protected final void fireVetoableChange(PropertyChangeEvent event)
              throws PropertyVetoException {
          VetoableChangeSupport aVetoSupport = this.vetoSupport;
          if (aVetoSupport == null) {
              return;
          }
          aVetoSupport.fireVetoableChange(event);
      }
docs: General support for reporting constrained property changes. Sends the given
  PropertyChangeEvent to any registered PropertyChangeListener.<p>
  
  Most bean setters will invoke the fireXXX methods that get a property name and the old and
  new value. However some frameworks and setters may prefer to use this general method. Also,
  this method allows to fire IndexedPropertyChangeEvents that have been introduced in Java 5.
  
  @param event describes the property change
  @throws PropertyVetoException if a constrained property change is rejected
  
  @since 1.3