--- old/src/java.desktop/share/classes/javax/swing/event/EventListenerList.java	2017-10-26 15:30:21.000000000 -0700
+++ new/src/java.desktop/share/classes/javax/swing/event/EventListenerList.java	2017-10-26 15:30:21.000000000 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2017, 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
@@ -102,7 +102,7 @@
     /* A null array to be shared by all empty listener lists*/
     private static final Object[] NULL_ARRAY = new Object[0];
     /** The list of ListenerType - Listener pairs */
-    protected transient Object[] listenerList = NULL_ARRAY;
+    protected volatile transient Object[] listenerList = NULL_ARRAY;
 
     /**
      * Passes back the event listener list as an array