--- old/src/share/classes/java/util/TreeMap.java	2013-08-26 20:48:28.809105289 -0700
+++ new/src/share/classes/java/util/TreeMap.java	2013-08-26 20:48:28.633105280 -0700
@@ -1012,7 +1012,7 @@
         int expectedModCount = modCount;
 
         for (Entry<K, V> e = getFirstEntry(); e != null; e = successor(e)) {
-            e.value = Objects.requireNonNull(function.apply(e.key, e.value));
+            e.value = function.apply(e.key, e.value);
 
             if (expectedModCount != modCount) {
                 throw new ConcurrentModificationException();