src/windows/classes/sun/awt/windows/WWindowPeer.java

*** 448,459 ****
       * Returns all the ever active windows from the current AppContext.
       * The list is sorted by the time of activation, so the latest
       * active window is always at the end.
       */
      @SuppressWarnings("unchecked")
!     public static long[] getActiveWindowHandles() {
!         AppContext appContext = AppContext.getAppContext();
          synchronized (appContext) {
              List<WWindowPeer> l = (List<WWindowPeer>)appContext.get(ACTIVE_WINDOWS_KEY);
              if (l == null) {
                  return null;
              }
--- 448,460 ----
       * Returns all the ever active windows from the current AppContext.
       * The list is sorted by the time of activation, so the latest
       * active window is always at the end.
       */
      @SuppressWarnings("unchecked")
!     public static long[] getActiveWindowHandles(Component target) {
!         AppContext appContext = SunToolkit.targetToAppContext(target);
!         if (appContext == null) return null;
          synchronized (appContext) {
              List<WWindowPeer> l = (List<WWindowPeer>)appContext.get(ACTIVE_WINDOWS_KEY);
              if (l == null) {
                  return null;
              }