--- a/src/hotspot/share/gc/g1/g1Arguments.hpp	Mon Mar 26 09:35:20 2018 -0400
+++ b/src/hotspot/share/gc/g1/g1Arguments.hpp	Mon Mar 26 12:44:39 2018 +0200
@@ -1,4 +1,5 @@
 /*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -30,9 +31,14 @@
 class CollectedHeap;
 
 class G1Arguments : public GCArguments {
+  friend class G1HeapVerifierTest_parse_Test;
+
+private:
+  static void initialize_verification_types();
+  static void parse_verification_type(const char* type);
+
 public:
   virtual void initialize_flags();
-  virtual bool parse_verification_type(const char* type);
   virtual size_t conservative_max_heap_alignment();
   virtual CollectedHeap* create_heap();
 };