if (ancestorListener != null) progressBar.removeAncestorListener(ancestorListener); ancestorListener = null;  if (componentListener != null) progressBar.removeComponentListener(componentListener); componentListener = null;
  protected void uninstallListeners()  {    progressBar.removeChangeListener(changeListener);    progressBar.removePropertyChangeListener(propertyListener);    animationTimer.removeActionListener(animation);    changeListener = null;    propertyListener = null;    animation = null;  }