--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/classfile/metadataOnStackMark.hpp	Wed Jan 23 10:34:29 2013 -0500
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2013, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_CLASSFILE_METADATAONSTACKMARK_HPP
+#define SHARE_VM_CLASSFILE_METADATAONSTACKMARK_HPP
+
+#include "memory/allocation.hpp"
+
+class Metadata;
+
+// Helper class to mark and unmark metadata used on the stack as either handles
+// or executing methods, so that it can't be deleted during class redefinition
+// and class unloading.
+// This is also used for other things that can be deallocated, like class
+// metadata during parsing, relocated methods, and methods in backtraces.
+class MetadataOnStackMark : public StackObj {
+  NOT_PRODUCT(static bool _is_active;)
+ public:
+  MetadataOnStackMark();
+  ~MetadataOnStackMark();
+  static void record(Metadata* m);
+};
+
+#endif // SHARE_VM_CLASSFILE_METADATAONSTACKMARK_HPP