code: protected final void fireIndexedPropertyChange(String propertyName, int index,
              boolean oldValue, boolean newValue) {
          if (oldValue == newValue) {
              return;
          }
          fireIndexedPropertyChange(propertyName, index,
                  Boolean.valueOf(oldValue), Boolean.valueOf(newValue));
      }
docs: Report a {@code boolean} bound indexed property update to any registered listeners.<p>
  
  No event is fired if old and new values are equal and non-null.<p>
  
  This is merely a convenience wrapper around the more general fireIndexedPropertyChange method
  which takes Object values.
  
  @param propertyName The programmatic name of the property that was changed.
  @param index index of the property element that was changed.
  @param oldValue The old value of the property.
  @param newValue The new value of the property.
  
  @since 2.0