1 /*
   2  * Copyright (c) 1999, 2010, 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_CI_CINULLOBJECT_HPP
  26 #define SHARE_VM_CI_CINULLOBJECT_HPP
  27 
  28 #include "ci/ciClassList.hpp"
  29 #include "ci/ciObject.hpp"
  30 #include "ci/ciUtilities.hpp"
  31 
  32 // ciNullObject
  33 //
  34 // This class represents a null reference in the VM.
  35 class ciNullObject : public ciObject {
  36   CI_PACKAGE_ACCESS
  37 
  38 private:
  39   ciNullObject() : ciObject() {}
  40 
  41   const char* type_string() { return "ciNullObject"; }
  42 
  43   void print_impl(outputStream* st);
  44 
  45 public:
  46   // Is this ciObject a Java Language Object?  That is,
  47   // is the ciObject an instance or an array
  48   bool is_java_object() { return true; }
  49 
  50   // What kind of ciObject is this?
  51   bool is_null_object() const { return true; }
  52   bool is_classless() const   { return true; }
  53 
  54   // Get the distinguished instance of this klass.
  55   static ciNullObject* make();
  56 };
  57 
  58 #endif // SHARE_VM_CI_CINULLOBJECT_HPP
--- EOF ---