1 /*
   2  * Copyright 2000-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *  
  23  */
  24 
  25 package sun.jvm.hotspot.oops;
  26 
  27 import java.util.*;
  28 import sun.jvm.hotspot.debugger.*;
  29 import sun.jvm.hotspot.memory.*;
  30 import sun.jvm.hotspot.runtime.*;
  31 import sun.jvm.hotspot.types.*;
  32 
  33 // Array is an abstract superclass for TypeArray and ObjArray
  34 
  35 public class Array extends Oop {
  36   static {
  37     VM.registerVMInitializedObserver(new Observer() {
  38         public void update(Observable o, Object data) {
  39           initialize(VM.getVM().getTypeDataBase());
  40         }
  41       });
  42   }
  43 
  44   Array(OopHandle handle, ObjectHeap heap) {
  45     super(handle, heap);
  46   }
  47 
  48   private static void initialize(TypeDataBase db) throws WrongTypeException {
  49     Type type   = db.lookupType("arrayOopDesc");
  50     length      = new CIntField(type.getCIntegerField("_length"), 0);
  51     headerSize  = type.getSize();
  52   }
  53 
  54   // Size of the arrayOopDesc
  55   private static long headerSize;
  56 
  57   // Fields
  58   private static CIntField length;
  59 
  60   // Accessors for declared fields
  61   public long getLength() { return length.getValue(this); }
  62 
  63   public long getObjectSize() {
  64     ArrayKlass klass = (ArrayKlass) getKlass();
  65     // We have to fetch the length of the array, shift (multiply) it
  66     // appropriately, up to wordSize, add the header, and align to
  67     // object size.
  68     long s = getLength() << klass.getLog2ElementSize();
  69     s += klass.getArrayHeaderInBytes();
  70     s = Oop.alignObjectSize(s);
  71     return s;
  72   }
  73 
  74   public static long baseOffsetInBytes(BasicType type) {
  75     if (Universe.elementTypeShouldBeAligned(type)) {
  76       return (VM.getVM().isLP64()) ?  alignObjectSize(headerSize) 
  77                                    : VM.getVM().alignUp(headerSize, 8);
  78     } else {
  79       return headerSize;
  80     }
  81   }
  82 
  83   public boolean isArray()             { return true; }
  84 
  85   public void iterateFields(OopVisitor visitor, boolean doVMFields) {
  86     super.iterateFields(visitor, doVMFields);
  87     if (doVMFields) {
  88       visitor.doCInt(length, true);
  89     }
  90   }
  91 }