1 /*
   2  * Copyright (c) 2000, 2015, 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.gc.serial;
  26 
  27 import java.io.*;
  28 import java.util.*;
  29 
  30 import sun.jvm.hotspot.debugger.*;
  31 import sun.jvm.hotspot.gc.shared.*;
  32 import sun.jvm.hotspot.runtime.*;
  33 import sun.jvm.hotspot.types.*;
  34 
  35 /** <P> TenuredGeneration models a heap of old objects contained
  36     in a single contiguous space. </P>
  37 
  38     <P> Garbage collection is performed using mark-compact. </P> */
  39 
  40 public class TenuredGeneration extends CardGeneration {
  41   private static AddressField theSpaceField;
  42 
  43   static {
  44     VM.registerVMInitializedObserver(new Observer() {
  45         public void update(Observable o, Object data) {
  46           initialize(VM.getVM().getTypeDataBase());
  47         }
  48       });
  49   }
  50 
  51   private static synchronized void initialize(TypeDataBase db) {
  52     Type type = db.lookupType("TenuredGeneration");
  53 
  54     theSpaceField = type.getAddressField("_the_space");
  55   }
  56 
  57   public TenuredGeneration(Address addr) {
  58     super(addr);
  59   }
  60 
  61   public ContiguousSpace theSpace() {
  62     return (ContiguousSpace) VMObjectFactory.newObject(ContiguousSpace.class, theSpaceField.getValue(addr));
  63   }
  64 
  65   public boolean isIn(Address p) {
  66     return theSpace().contains(p);
  67   }
  68 
  69   /** Space queries */
  70   public long capacity()            { return theSpace().capacity();                                }
  71   public long used()                { return theSpace().used();                                    }
  72   public long free()                { return theSpace().free();                                    }
  73   public long contiguousAvailable() { return theSpace().free() + virtualSpace().uncommittedSize(); }
  74 
  75   public void spaceIterate(SpaceClosure blk, boolean usedOnly) {
  76     blk.doSpace(theSpace());
  77   }
  78 
  79   public void liveRegionsIterate(LiveRegionsClosure closure) {
  80     closure.doLiveRegions(theSpace());
  81   }
  82 
  83   public void printOn(PrintStream tty) {
  84     tty.print("  old ");
  85     theSpace().printOn(tty);
  86   }
  87 
  88   public Generation.Name kind() {
  89     return Generation.Name.MARK_SWEEP_COMPACT;
  90   }
  91 
  92   public String name() {
  93     return "tenured generation";
  94   }
  95 }