code: final void firePropertyChange(String property, Object oldValue,
                                    Object newValue)
      {
          Object listeners = propertyListeners;
          if (listeners != null) {
              firePropertyChangeImpl(listeners, property, oldValue, newValue);
          }
      }
docs: Notify any registered listeners that a bounded property has changed
  @see #addPropertyChangeListener(java.beans.PropertyChangeListener)
  @see #removePropertyChangeListener(java.beans.PropertyChangeListener)
  @see java.beans.PropertyChangeListener
  @see java.beans.PropertyChangeEvent
  @param  property  the bound property
  @param  oldValue  the old value
  @param  newValue   the new value