/*

 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

package sun.jvm.hotspot.oops;

import java.util.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.memory.*;

import sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.types.*;

// Array is an abstract superclass for TypeArray and ObjArray

public class Array extends Oop {

  static {

    VM.registerVMInitializedObserver(new Observer() {

        public void update(Observable o, Object data) {

          initialize(VM.getVM().getTypeDataBase());

        }

      });

  }

  Array(OopHandle handle, ObjectHeap heap) {

    super(handle, heap);

  }

  private static void initialize(TypeDataBase db) throws WrongTypeException {

    Type type   = db.lookupType("arrayOopDesc");

    typeSize    = (int)type.getSize();

  }

  // Size of the arrayOopDesc

  private static long headerSize=0;

  private static long lengthOffsetInBytes=0;

  private static long typeSize;

  private static long headerSizeInBytes() {

    if (headerSize != 0) {

      return headerSize;

    }

    if (VM.getVM().isCompressedKlassPointersEnabled()) {

      headerSize = typeSize;

    } else {

      headerSize = VM.getVM().alignUp(typeSize + VM.getVM().getIntSize(),

                                      VM.getVM().getHeapWordSize());

    }

    return headerSize;

  }

  private static long headerSize(BasicType type) {

    if (Universe.elementTypeShouldBeAligned(type)) {

       return alignObjectSize(headerSizeInBytes())/VM.getVM().getHeapWordSize();

    } else {

      return headerSizeInBytes()/VM.getVM().getHeapWordSize();

    }

  }

  private long lengthOffsetInBytes() {

    if (lengthOffsetInBytes != 0) {

      return lengthOffsetInBytes;

    }

    if (VM.getVM().isCompressedKlassPointersEnabled()) {

      lengthOffsetInBytes = typeSize - VM.getVM().getIntSize();

    } else {

      lengthOffsetInBytes = typeSize;

    }

    return lengthOffsetInBytes;

  }

  // Accessors for declared fields

  public long getLength() {

    boolean isUnsigned = true;

    return this.getHandle().getCIntegerAt(lengthOffsetInBytes(), VM.getVM().getIntSize(), isUnsigned);

  }

  public long getObjectSize() {

    ArrayKlass klass = (ArrayKlass) getKlass();

    // We have to fetch the length of the array, shift (multiply) it

    // appropriately, up to wordSize, add the header, and align to

    // object size.

    long s = getLength() << klass.getLog2ElementSize();

    s += klass.getArrayHeaderInBytes();

    s = Oop.alignObjectSize(s);

    return s;

  }

  public static long baseOffsetInBytes(BasicType type) {

    return headerSize(type) * VM.getVM().getHeapWordSize();

  }

  public boolean isArray()             { return true; }

  public void iterateFields(OopVisitor visitor, boolean doVMFields) {

    super.iterateFields(visitor, doVMFields);

  }

}