--- a/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/tree/JCTree.java	Wed Jul 05 20:22:22 2017 +0200
+++ b/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/tree/JCTree.java	Fri Feb 27 11:51:53 2015 +0000
@@ -2443,8 +2443,7 @@
         public TypeBoundKind kind;
         public JCTree inner;
         protected JCWildcard(TypeBoundKind kind, JCTree inner) {
-            kind.getClass(); // null-check
-            this.kind = kind;
+            this.kind = Assert.checkNonNull(kind);
             this.inner = inner;
         }
         @Override