src/java.desktop/share/classes/javax/swing/plaf/metal/MetalToolBarUI.java

*** 86,96 ****
      private JMenuBar lastMenuBar;
  
      /**
       * Registers the specified component.
       */
!     synchronized static void register(JComponent c) {
          if (c == null) {
              // Exception is thrown as convenience for callers that are
              // typed to throw an NPE.
              throw new NullPointerException("JComponent must be non-null");
          }
--- 86,96 ----
      private JMenuBar lastMenuBar;
  
      /**
       * Registers the specified component.
       */
!     static synchronized void register(JComponent c) {
          if (c == null) {
              // Exception is thrown as convenience for callers that are
              // typed to throw an NPE.
              throw new NullPointerException("JComponent must be non-null");
          }
*** 98,108 ****
      }
  
      /**
       * Unregisters the specified component.
       */
!     synchronized static void unregister(JComponent c) {
          for (int counter = components.size() - 1; counter >= 0; counter--) {
              // Search for the component, removing any flushed references
              // along the way.
              JComponent target = components.get(counter).get();
  
--- 98,108 ----
      }
  
      /**
       * Unregisters the specified component.
       */
!     static synchronized void unregister(JComponent c) {
          for (int counter = components.size() - 1; counter >= 0; counter--) {
              // Search for the component, removing any flushed references
              // along the way.
              JComponent target = components.get(counter).get();
  
*** 114,124 ****
  
      /**
       * Finds a previously registered component of class <code>target</code>
       * that shares the JRootPane ancestor of <code>from</code>.
       */
!     synchronized static Object findRegisteredComponentOfType(JComponent from,
                                                               Class<?> target) {
          JRootPane rp = SwingUtilities.getRootPane(from);
          if (rp != null) {
              for (int counter = components.size() - 1; counter >= 0; counter--){
                  Object component = ((WeakReference)components.get(counter)).
--- 114,124 ----
  
      /**
       * Finds a previously registered component of class <code>target</code>
       * that shares the JRootPane ancestor of <code>from</code>.
       */
!     static synchronized Object findRegisteredComponentOfType(JComponent from,
                                                               Class<?> target) {
          JRootPane rp = SwingUtilities.getRootPane(from);
          if (rp != null) {
              for (int counter = components.size() - 1; counter >= 0; counter--){
                  Object component = ((WeakReference)components.get(counter)).