1 /*
   2  * Copyright (c) 2000, 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 package sun.jvm.hotspot.memory;
  26 
  27 import java.io.*;
  28 import java.util.*;
  29 
  30 import sun.jvm.hotspot.debugger.*;
  31 import sun.jvm.hotspot.runtime.*;
  32 import sun.jvm.hotspot.types.*;
  33 
  34 /** <P> TenuredGeneration models a heap of old objects contained
  35     in a single contiguous space. </P>
  36 
  37     <P> Garbage collection is performed using mark-compact. </P> */
  38 
  39 public class TenuredGeneration extends CardGeneration {
  40   private static AddressField theSpaceField;
  41 
  42   static {
  43     VM.registerVMInitializedObserver(new Observer() {
  44         public void update(Observable o, Object data) {
  45           initialize(VM.getVM().getTypeDataBase());
  46         }
  47       });
  48   }
  49 
  50   private static synchronized void initialize(TypeDataBase db) {
  51     Type type = db.lookupType("TenuredGeneration");
  52 
  53     theSpaceField = type.getAddressField("_the_space");
  54   }
  55 
  56   public TenuredGeneration(Address addr) {
  57     super(addr);
  58   }
  59 
  60   public ContiguousSpace theSpace() {
  61     return (ContiguousSpace) VMObjectFactory.newObject(ContiguousSpace.class, theSpaceField.getValue(addr));
  62   }
  63 
  64   public boolean isIn(Address p) {
  65     return theSpace().contains(p);
  66   }
  67 
  68   /** Space queries */
  69   public long capacity()            { return theSpace().capacity();                                }
  70   public long used()                { return theSpace().used();                                    }
  71   public long free()                { return theSpace().free();                                    }
  72   public long contiguousAvailable() { return theSpace().free() + virtualSpace().uncommittedSize(); }
  73 
  74   public void spaceIterate(SpaceClosure blk, boolean usedOnly) {
  75     blk.doSpace(theSpace());
  76   }
  77 
  78   public void printOn(PrintStream tty) {
  79     tty.print("  old ");
  80     theSpace().printOn(tty);
  81   }
  82 
  83   public Generation.Name kind() {
  84     return Generation.Name.MARK_SWEEP_COMPACT;
  85   }
  86 
  87   public String name() {
  88     return "tenured generation";
  89   }
  90 }