src/share/classes/sun/awt/SunToolkit.java

*** 542,585 ****
                  }
              }, PeerEvent.ULTIMATE_PRIORITY_EVENT);
          postEvent(targetToAppContext(e.getSource()), pe);
      }
  
-     protected static final Lock flushLock = new ReentrantLock();
-     private static boolean isFlushingPendingEvents = false;
- 
      /*
       * Flush any pending events which haven't been posted to the AWT
       * EventQueue yet.
       */
      public static void flushPendingEvents()  {
-         flushLock.lock();
-         try {
-             // Don't call flushPendingEvents() recursively
-             if (!isFlushingPendingEvents) {
-                 isFlushingPendingEvents = true;
                  AppContext appContext = AppContext.getAppContext();
!                 PostEventQueue postEventQueue =
!                     (PostEventQueue)appContext.get(POST_EVENT_QUEUE_KEY);
!                 if (postEventQueue != null) {
!                     postEventQueue.flush();
!                 }
!             }
!         } finally {
!             isFlushingPendingEvents = false;
!             flushLock.unlock();
!         }
      }
  
!     public static boolean isPostEventQueueEmpty()  {
!         AppContext appContext = AppContext.getAppContext();
          PostEventQueue postEventQueue =
              (PostEventQueue)appContext.get(POST_EVENT_QUEUE_KEY);
          if (postEventQueue != null) {
!             return postEventQueue.noEvents();
!         } else {
!             return true;
          }
      }
  
      /*
       * Execute a chunk of code on the Java event handler thread for the
--- 542,570 ----
                  }
              }, PeerEvent.ULTIMATE_PRIORITY_EVENT);
          postEvent(targetToAppContext(e.getSource()), pe);
      }
  
      /*
       * Flush any pending events which haven't been posted to the AWT
       * EventQueue yet.
       */
      public static void flushPendingEvents()  {
          AppContext appContext = AppContext.getAppContext();
!         flushPendingEvents(appContext);
      }
  
!     /*
!      * Flush the PostEventQueue for the right AppContext.
!      * The default flushPendingEvents only flushes the thread-local context,
!      * which is not always correct, c.f. 3746956
!      */
!     public static void flushPendingEvents(AppContext appContext) {
          PostEventQueue postEventQueue =
                  (PostEventQueue)appContext.get(POST_EVENT_QUEUE_KEY);
          if (postEventQueue != null) {
!             postEventQueue.flush();
          }
      }
  
      /*
       * Execute a chunk of code on the Java event handler thread for the
*** 2110,2155 ****
  class PostEventQueue {
      private EventQueueItem queueHead = null;
      private EventQueueItem queueTail = null;
      private final EventQueue eventQueue;
  
!     // For the case when queue is cleared but events are not posted
!     private volatile boolean isFlushing = false;
  
      PostEventQueue(EventQueue eq) {
          eventQueue = eq;
      }
  
-     public synchronized boolean noEvents() {
-         return queueHead == null && !isFlushing;
-     }
- 
      /*
       * Continually post pending AWTEvents to the Java EventQueue. The method
       * is synchronized to ensure the flush is completed before a new event
       * can be posted to this queue.
       *
       * 7177040: The method couldn't be wholly synchronized because of calls
       * of EventQueue.postEvent() that uses pushPopLock, otherwise it could
       * potentially lead to deadlock
       */
      public void flush() {
          EventQueueItem tempQueue;
          synchronized (this) {
              tempQueue = queueHead;
              queueHead = queueTail = null;
-             isFlushing = true;
          }
-         try {
              while (tempQueue != null) {
                  eventQueue.postEvent(tempQueue.event);
                  tempQueue = tempQueue.next;
              }
          }
          finally {
              isFlushing = false;
          }
      }
  
      /*
       * Enqueue an AWTEvent to be posted to the Java EventQueue.
       */
--- 2095,2155 ----
  class PostEventQueue {
      private EventQueueItem queueHead = null;
      private EventQueueItem queueTail = null;
      private final EventQueue eventQueue;
  
!     // For synchronization of flush() method call
!     private boolean isFlushing = false;
! 
!     // For elimination of recursion of flush() method call
!     private final ThreadLocal<Boolean> isThreadLocalFlushing = new ThreadLocal<>();
  
      PostEventQueue(EventQueue eq) {
          eventQueue = eq;
      }
  
      /*
       * Continually post pending AWTEvents to the Java EventQueue. The method
       * is synchronized to ensure the flush is completed before a new event
       * can be posted to this queue.
       *
       * 7177040: The method couldn't be wholly synchronized because of calls
       * of EventQueue.postEvent() that uses pushPopLock, otherwise it could
       * potentially lead to deadlock
       */
      public void flush() {
+         Boolean b = isThreadLocalFlushing.get();
+         if (b != null && b) {
+             return;
+         }
+ 
+         isThreadLocalFlushing.set(true);
+         try {
              EventQueueItem tempQueue;
              synchronized (this) {
+                 while (isFlushing) {
+                    wait();
+                 }
+                 isFlushing = (queueHead != null);
+ 
                  tempQueue = queueHead;
                  queueHead = queueTail = null;
              }
              while (tempQueue != null) {
                  eventQueue.postEvent(tempQueue.event);
                  tempQueue = tempQueue.next;
              }
          }
+         catch (InterruptedException e) {
+         }
          finally {
+             synchronized (this) {
                  isFlushing = false;
+                 notifyAll();
+             }
          }
+         isThreadLocalFlushing.set(false);
      }
  
      /*
       * Enqueue an AWTEvent to be posted to the Java EventQueue.
       */