1 /*
   2  * Copyright (c) 1997, 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_OOPS_KLASSKLASS_HPP
  26 #define SHARE_VM_OOPS_KLASSKLASS_HPP
  27 
  28 #include "memory/oopFactory.hpp"
  29 #include "oops/klass.hpp"
  30 #include "oops/klassOop.hpp"
  31 
  32 // A klassKlass serves as the fix point of the klass chain.
  33 // The klass of klassKlass is itself.
  34 
  35 class klassKlass: public Klass {
  36   friend class VMStructs;
  37  private:
  38   juint    _alloc_size;        // allocation profiling support
  39  public:
  40   // Testing
  41   bool oop_is_klass()  const { return true; }
  42   bool is_leaf_class() const { return true; }
  43 
  44   // Sizing
  45   int oop_size(oop obj) const;
  46   int klass_oop_size() const { return object_size(); }
  47 
  48   // Allocation
  49   DEFINE_ALLOCATE_PERMANENT(klassKlass);
  50   static klassOop create_klass(TRAPS );
  51 
  52   // Casting from klassOop
  53   static klassKlass* cast(klassOop k) {
  54     assert(k->klass_part()->oop_is_klass(), "cast to klassKlass");
  55     return (klassKlass*) k->klass_part();
  56   }
  57 
  58   // Sizing
  59   static int header_size()  { return oopDesc::header_size() + sizeof(klassKlass)/HeapWordSize; }
  60   int object_size() const   { return align_object_size(header_size()); }
  61 
  62   // Garbage collection
  63   void oop_follow_contents(oop obj);
  64   int  oop_adjust_pointers(oop obj);
  65 
  66   // Parallel Scavenge and Parallel Old
  67   PARALLEL_GC_DECLS
  68 
  69   // Iterators
  70   int  oop_oop_iterate(oop obj, OopClosure* blk);
  71   int  oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr);
  72 
  73   // Allocation profiling support
  74   juint alloc_size() const              { return _alloc_size; }
  75   void set_alloc_size(juint n)          { _alloc_size = n; }
  76 
  77   // Printing
  78   void oop_print_value_on(oop obj, outputStream* st);
  79   void oop_print_on      (oop obj, outputStream* st);
  80 
  81   // Verification
  82   const char* internal_name() const;
  83   void oop_verify_on(oop obj, outputStream* st);
  84 };
  85 
  86 #endif // SHARE_VM_OOPS_KLASSKLASS_HPP