code: public final synchronized void removeVetoableChangeListener(
              String propertyName,
              VetoableChangeListener listener) {
          if (listener == null || vetoSupport == null) {
              return;
          }
          vetoSupport.removeVetoableChangeListener(propertyName, listener);
      }
docs: Removes a VetoableChangeListener from the listener list for a specific property. This method
  should be used to remove VetoableChangeListeners that were registered for a specific bound
  property.<p>
  
  If listener is {@code null}, no exception is thrown and no action is performed.
  
  @param propertyName a valid property name
  @param listener the VetoableChangeListener to be removed
  
  @see #addVetoableChangeListener(String, VetoableChangeListener)
  @see #removeVetoableChangeListener(VetoableChangeListener)
  @see #getVetoableChangeListeners(String)