src/java.desktop/unix/classes/sun/awt/X11/XRootWindow.java

*** 29,52 ****
   * This class represents AWT application root window functionality.
   * Object of this class is singleton, all window reference it to have
   * common logical ancestor
   */
  class XRootWindow extends XBaseWindow {
!     private static XRootWindow xawtRootWindow = null;
!     static XRootWindow getInstance() {
          XToolkit.awtLock();
          try {
-             if (xawtRootWindow == null) {
                  xawtRootWindow = new XRootWindow();
                  xawtRootWindow.init(xawtRootWindow.getDelayedParams().delete(DELAYED));
-             }
-             return xawtRootWindow;
          } finally {
              XToolkit.awtUnlock();
          }
      }
  
      private XRootWindow() {
          super(new XCreateWindowParams(new Object[] { DELAYED, Boolean.TRUE,
                                                       EVENT_MASK, XConstants.StructureNotifyMask }));
      }
  
--- 29,56 ----
   * This class represents AWT application root window functionality.
   * Object of this class is singleton, all window reference it to have
   * common logical ancestor
   */
  class XRootWindow extends XBaseWindow {
!     private static class LazyHolder {
!         private static final XRootWindow xawtRootWindow;
! 
!         static {
              XToolkit.awtLock();
              try {
                  xawtRootWindow = new XRootWindow();
                  xawtRootWindow.init(xawtRootWindow.getDelayedParams().delete(DELAYED));
              } finally {
                  XToolkit.awtUnlock();
              }
          }
  
+     }
+     static XRootWindow getInstance() {
+         return LazyHolder.xawtRootWindow;
+     }
+ 
      private XRootWindow() {
          super(new XCreateWindowParams(new Object[] { DELAYED, Boolean.TRUE,
                                                       EVENT_MASK, XConstants.StructureNotifyMask }));
      }