1 /*
   2  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_UTILITIES_TRAITS_IS_CLASS_OR_UNION_HPP
  26 #define SHARE_VM_UTILITIES_TRAITS_IS_CLASS_OR_UNION_HPP
  27 
  28 /**
  29  * IsClassOrUnion<T>::value is true iff the type T is a class or union type.
  30  */
  31 template<typename T>
  32 class IsClassOrUnion {
  33   typedef char yes[1];
  34   typedef char no[2];
  35 
  36   template<typename U>
  37   static yes &check(int U::*);
  38 
  39   template<typename>
  40   static no &check(...);
  41 
  42 public:
  43   static const bool value = (sizeof(check<T>(0)) == sizeof(yes));
  44 };
  45 
  46 #endif // SHARE_VM_UTILITIES_TRAITS_IS_CLASS_OR_UNION_HPP
  47