1 /*
   2  * Copyright (c) 2000, 2019, 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.shared;
  26 
  27 import java.io.*;
  28 import java.util.*;
  29 
  30 import sun.jvm.hotspot.debugger.*;
  31 import sun.jvm.hotspot.memory.*;
  32 import sun.jvm.hotspot.runtime.*;
  33 import sun.jvm.hotspot.types.*;
  34 import sun.jvm.hotspot.utilities.BitMapInterface;
  35 import sun.jvm.hotspot.utilities.BitMapSegmented;
  36 
  37 public abstract class CollectedHeap extends VMObject {
  38   private static long         reservedFieldOffset;
  39 
  40   static {
  41     VM.registerVMInitializedObserver(new Observer() {
  42         public void update(Observable o, Object data) {
  43           initialize(VM.getVM().getTypeDataBase());
  44         }
  45       });
  46   }
  47 
  48   private static synchronized void initialize(TypeDataBase db) {
  49     Type type = db.lookupType("CollectedHeap");
  50 
  51     reservedFieldOffset = type.getField("_reserved").getOffset();
  52   }
  53 
  54   public CollectedHeap(Address addr) {
  55     super(addr);
  56   }
  57 
  58   /** Returns the lowest address of the heap. */
  59   public Address start() {
  60     return reservedRegion().start();
  61   }
  62 
  63   public abstract long capacity();
  64   public abstract long used();
  65 
  66   public MemRegion reservedRegion() {
  67     return new MemRegion(addr.addOffsetTo(reservedFieldOffset));
  68   }
  69 
  70   public boolean isIn(Address a) {
  71     return isInReserved(a);
  72   }
  73 
  74   public boolean isInReserved(Address a) {
  75     return reservedRegion().contains(a);
  76   }
  77 
  78   public abstract CollectedHeapName kind();
  79 
  80   public String oopAddressDescription(OopHandle handle) {
  81       return handle.toString();
  82   }
  83 
  84   public OopHandle oop_load_at(OopHandle handle, long offset) {
  85       return handle.getOopHandleAt(offset);
  86   }
  87 
  88   public OopHandle oop_load_in_native(Address addr) {
  89       return addr.getOopHandleAt(0);
  90   }
  91 
  92   public void print() { printOn(System.out); }
  93   public void printOn(PrintStream tty) {
  94     MemRegion mr = reservedRegion();
  95     tty.println("unknown subtype of CollectedHeap @ " + getAddress() + " (" +
  96                 mr.start() + "," + mr.end() + ")");
  97   }
  98 
  99   public BitMapInterface createBitMap(long bits) {
 100     return new BitMapSegmented(bits);
 101   }
 102 }