--- a/jdk/src/java.desktop/share/classes/sun/awt/SunToolkit.java	Tue Oct 18 12:43:07 2016 +0300
+++ b/jdk/src/java.desktop/share/classes/sun/awt/SunToolkit.java	Tue Oct 18 18:00:22 2016 +0300
@@ -1512,9 +1512,9 @@
      */
     protected abstract boolean syncNativeQueue(final long timeout);
 
-    private boolean eventDispatched = false;
-    private boolean queueEmpty = false;
-    private final Object waitLock = "Wait Lock";
+    private boolean eventDispatched;
+    private boolean queueEmpty;
+    private final Object waitLock = new Object();
 
     private boolean isEQEmpty() {
         EventQueue queue = getSystemEventQueueImpl();
@@ -1531,10 +1531,11 @@
     @SuppressWarnings("serial")
     protected final boolean waitForIdle(final long timeout) {
         flushPendingEvents();
-        boolean queueWasEmpty = isEQEmpty();
-        queueEmpty = false;
-        eventDispatched = false;
-        synchronized(waitLock) {
+        final boolean queueWasEmpty;
+        synchronized (waitLock) {
+            queueWasEmpty = isEQEmpty();
+            queueEmpty = false;
+            eventDispatched = false;
             postEvent(AppContext.getAppContext(),
                       new PeerEvent(getSystemEventQueueImpl(), null, PeerEvent.LOW_PRIORITY_EVENT) {
                           @Override

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/Robot/WaitForIdleSyncroizedOnString/WaitForIdleSyncroizedOnString.java	Tue Oct 18 18:00:22 2016 +0300
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.awt.Robot;
+import java.util.concurrent.CountDownLatch;
+
+import javax.swing.SwingUtilities;
+
+/**
+ * @test
+ * @key headful
+ * @bug 8166673
+ */
+public final class WaitForIdleSyncroizedOnString {
+
+    private static final String WAIT_LOCK = "Wait Lock";
+
+    private static volatile boolean passed = true;
+
+    public static void main(final String[] args) throws Exception {
+        CountDownLatch go = new CountDownLatch(1);
+        Robot r = new Robot();
+        SwingUtilities.invokeLater(() -> System.out.println("some work"));
+        Thread t = new Thread(() -> {
+            synchronized (WAIT_LOCK) {
+                go.countDown();
+                try {
+                    Thread.sleep(30000);
+                    passed = false;
+                } catch (InterruptedException e) {
+                    System.out.println("e = " + e);
+                }
+            }
+        });
+        t.start();
+        go.await();
+        r.waitForIdle();
+        t.interrupt();
+        if (!passed) {
+            throw new RuntimeException("Test failed");
+        }
+    }
+}