src/java.desktop/share/classes/java/awt/DefaultKeyboardFocusManager.java

@@ -262,17 +262,19 @@
             if (targetAppContext.isDisposed()) {
                 return false;
             }
             SunToolkit.postEvent(targetAppContext, se);
             if (EventQueue.isDispatchThread()) {
+                if (Thread.currentThread() instanceof EventDispatchThread) {
                 EventDispatchThread edt = (EventDispatchThread)
                     Thread.currentThread();
                 edt.pumpEvents(SentEvent.ID, new Conditional() {
                         public boolean evaluate() {
                             return !se.dispatched && !targetAppContext.isDisposed();
                         }
                     });
+                }
             } else {
                 synchronized (se) {
                     while (!se.dispatched && !targetAppContext.isDisposed()) {
                         try {
                             se.wait(1000);