/*

 * 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.gc.g1;

import java.util.Observable;

import java.util.Observer;

import sun.jvm.hotspot.debugger.Address;

import sun.jvm.hotspot.runtime.VM;

import sun.jvm.hotspot.runtime.VMObject;

import sun.jvm.hotspot.types.CIntegerField;

import sun.jvm.hotspot.types.Type;

import sun.jvm.hotspot.types.TypeDataBase;

// Mirror class for HeapRegionType. Currently we don't actually include

// any of its fields but only iterate over it.

public class HeapRegionType extends VMObject {

    private static int freeTag;

    private static int youngMask;

    private static int humongousMask;

    private static int pinnedMask;

    private static int oldMask;

    private static CIntegerField tagField;

    private int tag;

    static {

        VM.registerVMInitializedObserver(new Observer() {

                public void update(Observable o, Object data) {

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

                }

        });

    }

    private static synchronized void initialize(TypeDataBase db) {

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

        tagField = type.getCIntegerField("_tag");

        freeTag = db.lookupIntConstant("HeapRegionType::FreeTag");

        youngMask = db.lookupIntConstant("HeapRegionType::YoungMask");

        humongousMask = db.lookupIntConstant("HeapRegionType::HumongousMask");

        pinnedMask = db.lookupIntConstant("HeapRegionType::PinnedMask");

        oldMask = db.lookupIntConstant("HeapRegionType::OldMask");

    }

    public boolean isFree() {

        return tagField.getValue(addr) == freeTag;

    }

    public boolean isYoung() {

        return (tagField.getValue(addr) & youngMask) != 0;

    }

    public boolean isHumongous() {

        return (tagField.getValue(addr) & humongousMask) != 0;

    }

    public boolean isPinned() {

        return (tagField.getValue(addr) & pinnedMask) != 0;

    }

    public boolean isOld() {

        return (tagField.getValue(addr) & oldMask) != 0;

    }

    public HeapRegionType(Address addr) {

        super(addr);

    }

}