1 #ifdef USE_PRAGMA_IDENT_HDR
   2 #pragma ident "@(#)permGen.hpp  1.38 07/05/29 09:44:16 JVM"
   3 #endif
   4 /*
   5  * Copyright 2000-2008 Sun Microsystems, Inc.  All Rights Reserved.
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This code is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License version 2 only, as
  10  * published by the Free Software Foundation.
  11  *
  12  * This code is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  * version 2 for more details (a copy is included in the LICENSE file that
  16  * accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License version
  19  * 2 along with this work; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *  
  26  */
  27 
  28 // All heaps contains a "permanent generation," containing permanent
  29 // (reflective) objects.  This is like a regular generation in some ways,
  30 // but unlike one in others, and so is split apart.
  31 
  32 class Generation;
  33 class GenRemSet;
  34 class CSpaceCounters;
  35 
  36 // PermGen models the part of the heap 
  37 
  38 class PermGen : public CHeapObj {
  39   friend class VMStructs;
  40  protected:
  41   size_t _capacity_expansion_limit;  // maximum expansion allowed without a
  42                                      // full gc occuring
  43 
  44   HeapWord* mem_allocate_in_gen(size_t size, Generation* gen);
  45 
  46  public:
  47   enum Name {
  48     MarkSweepCompact, MarkSweep, ConcurrentMarkSweep
  49   };
  50 
  51   // Permanent allocation (initialized)  
  52   virtual HeapWord* mem_allocate(size_t size) = 0;
  53 
  54   // Mark sweep support
  55   virtual void compute_new_size() = 0;
  56 
  57   // Ideally, we would use MI (IMHO) but we'll do delegation instead.
  58   virtual Generation* as_gen() const = 0;
  59 
  60   virtual void oop_iterate(OopClosure* cl) {
  61     Generation* g = as_gen();
  62     assert(g != NULL, "as_gen() NULL");
  63     g->oop_iterate(cl);
  64   }
  65 
  66   virtual void object_iterate(ObjectClosure* cl) {
  67     Generation* g = as_gen();
  68     assert(g != NULL, "as_gen() NULL");
  69     g->object_iterate(cl);
  70   }
  71 
  72   // Performance Counter support
  73   virtual void update_counters() {
  74     Generation* g = as_gen();
  75     assert(g != NULL, "as_gen() NULL");
  76     g->update_counters();
  77   }
  78 };
  79