throw new Error("not implemented");
Component focusComp = (comp == null) ? getGlobalFocusOwner () : comp; Container focusCycleRoot = focusComp.getFocusCycleRootAncestor (); FocusTraversalPolicy policy = focusCycleRoot.getFocusTraversalPolicy ();  Component previous = policy.getComponentBefore (focusCycleRoot, focusComp); previous.requestFocusInWindow ();
  public void focusPreviousComponent(Component comp)  {    throw new Error("not implemented");  }