diff -Nru openjdk.orig/jdk/src/share/classes/sun/awt/AppContext.java openjdk/jdk/src/share/classes/sun/awt/AppContext.java
--- openjdk.orig/jdk/src/share/classes/sun/awt/AppContext.java	2013-08-05 16:49:37.120128300 +0100
+++ openjdk/jdk/src/share/classes/sun/awt/AppContext.java	2013-08-05 17:02:51.304664462 +0100
@@ -151,7 +151,7 @@
        contained in another AppContext. It is implicitly created for
        standalone apps only (i.e. not applets)
     */
-    private static AppContext mainAppContext = null;
+    private static volatile AppContext mainAppContext = null;
 
     /*
      * The hash map associated with this AppContext.  A private delegate
@@ -223,14 +223,15 @@
         threadGroup2appContext.put(threadGroup, this);
 
         this.contextClassLoader =
-            (ClassLoader) AccessController.doPrivileged(new PrivilegedAction() {
-                    public Object run() {
+             AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
+                    public ClassLoader run() {
                         return Thread.currentThread().getContextClassLoader();
                     }
                 });
     }
 
-    private static MostRecentThreadAppContext mostRecentThreadAppContext = null;
+    private static final ThreadLocal<AppContext> threadAppContext =
+            new ThreadLocal<AppContext>();
 
     private final static void initMainAppContext() {
         // On the main Thread, we get the ThreadGroup, make a corresponding
@@ -270,30 +271,18 @@
             return mainAppContext;
         }
 
-        final Thread currentThread = Thread.currentThread();
+        AppContext appContext = threadAppContext.get();
 
-        AppContext appContext = null;
-
-        // Note: this most recent Thread/AppContext caching is thread-hot.
-        // A simple test using SwingSet found that 96.8% of lookups
-        // were matched using the most recent Thread/AppContext.  By
-        // instantiating a simple MostRecentThreadAppContext object on
-        // cache misses, the cache hits can be processed without
-        // synchronization.
-
-        MostRecentThreadAppContext recent = mostRecentThreadAppContext;
-        if ((recent != null) && (recent.thread == currentThread))  {
-            appContext = recent.appContext; // Cache hit
-        } else {
-            appContext = (AppContext)AccessController.doPrivileged(
-                                            new PrivilegedAction() {
-            public Object run() {
-            // Get the current ThreadGroup, and look for it and its
-            // parents in the hash from ThreadGroup to AppContext --
-            // it should be found, because we use createNewContext()
-            // when new AppContext objects are created.
-            ThreadGroup currentThreadGroup = currentThread.getThreadGroup();
-            ThreadGroup threadGroup = currentThreadGroup;
+        if (null == appContext) {
+            appContext = AccessController.doPrivileged(new PrivilegedAction<AppContext>()
+            {
+                public AppContext run() {
+                    // Get the current ThreadGroup, and look for it and its
+                    // parents in the hash from ThreadGroup to AppContext --
+                    // it should be found, because we use createNewContext()
+                    // when new AppContext objects are created.
+                    ThreadGroup currentThreadGroup = Thread.currentThread().getThreadGroup();
+                    ThreadGroup threadGroup = currentThreadGroup;
 
                     // Special case: we implicitly create the main app context
                     // if no contexts have been created yet. This covers standalone apps
@@ -308,28 +297,29 @@
                         }
                     }
 
-            AppContext context = threadGroup2appContext.get(threadGroup);
-            while (context == null) {
-                threadGroup = threadGroup.getParent();
-                if (threadGroup == null) {
-		    return null;
+                    AppContext context = threadGroup2appContext.get(threadGroup);
+                    while (context == null) {
+                        threadGroup = threadGroup.getParent();
+                        if (threadGroup == null) {
+                            return null;
+                        }
+                        context = threadGroup2appContext.get(threadGroup);
+                    }
+
+                    // In case we did anything in the above while loop, we add
+                    // all the intermediate ThreadGroups to threadGroup2appContext
+                    // so we won't spin again.
+                    for (ThreadGroup tg = currentThreadGroup; tg != threadGroup; tg = tg.getParent()) {
+                        threadGroup2appContext.put(tg, context);
+                    }
+
+                    // Now we're done, so we cache the latest key/value pair.
+                    threadAppContext.set(context);
+
+
+                    return context;
                 }
-                context = threadGroup2appContext.get(threadGroup);
-            }
-            // In case we did anything in the above while loop, we add
-            // all the intermediate ThreadGroups to threadGroup2appContext
-            // so we won't spin again.
-            for (ThreadGroup tg = currentThreadGroup; tg != threadGroup; tg = tg.getParent()) {
-                threadGroup2appContext.put(tg, context);
-            }
-
-            // Now we're done, so we cache the latest key/value pair.
-            mostRecentThreadAppContext =
-                new MostRecentThreadAppContext(currentThread, context);
-
-            return context;
-          }
-         });
+            });
         }
 
         return appContext;
@@ -473,7 +463,7 @@
         // Threads in the ThreadGroup to exit.
 
         long startTime = System.currentTimeMillis();
-        long endTime = startTime + (long)THREAD_INTERRUPT_TIMEOUT;
+        long endTime = startTime + THREAD_INTERRUPT_TIMEOUT;
         while ((this.threadGroup.activeCount() > 0) &&
                (System.currentTimeMillis() < endTime)) {
             try {
@@ -488,7 +478,7 @@
         // Threads in the ThreadGroup to die.
 
         startTime = System.currentTimeMillis();
-        endTime = startTime + (long)THREAD_INTERRUPT_TIMEOUT;
+        endTime = startTime + THREAD_INTERRUPT_TIMEOUT;
         while ((this.threadGroup.activeCount() > 0) &&
                (System.currentTimeMillis() < endTime)) {
             try {
@@ -507,10 +497,7 @@
         }
         threadGroup2appContext.remove(this.threadGroup);
 
-        MostRecentThreadAppContext recent = mostRecentThreadAppContext;
-        if ((recent != null) && (recent.appContext == this))
-            mostRecentThreadAppContext = null;
-                // If the "most recent" points to this, clear it for GC
+        threadAppContext.set(null);
 
         // Finally, we destroy the ThreadGroup entirely.
         try {
@@ -693,6 +680,7 @@
      * Returns a string representation of this AppContext.
      * @since   1.2
      */
+    @Override
     public String toString() {
         return getClass().getName() + "[threadGroup=" + threadGroup.getName() + "]";
     }
@@ -842,15 +830,6 @@
     }
 }
 
-final class MostRecentThreadAppContext {
-    final Thread thread;
-    final AppContext appContext;
-    MostRecentThreadAppContext(Thread key, AppContext value) {
-        thread = key;
-        appContext = value;
-    }
-}
-
 final class MostRecentKeyValue {
     Object key;
     Object value;