/*

 * Copyright (c) 2011, 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.

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 */

package sun.jvm.hotspot.gc_implementation.g1;

import java.util.Iterator;

import java.util.Observable;

import java.util.Observer;

import sun.jvm.hotspot.debugger.Address;

import sun.jvm.hotspot.gc_interface.CollectedHeapName;

import sun.jvm.hotspot.memory.MemRegion;

import sun.jvm.hotspot.memory.SharedHeap;

import sun.jvm.hotspot.memory.SpaceClosure;

import sun.jvm.hotspot.runtime.VM;

import sun.jvm.hotspot.runtime.VMObjectFactory;

import sun.jvm.hotspot.types.AddressField;

import sun.jvm.hotspot.types.CIntegerField;

import sun.jvm.hotspot.types.Type;

import sun.jvm.hotspot.types.TypeDataBase;

// Mirror class for G1CollectedHeap.

public class G1CollectedHeap extends SharedHeap {

    // HeapRegionSeq _seq;

    static private long hrsFieldOffset;

    // MemRegion _g1_committed;

    static private long g1CommittedFieldOffset;

    // size_t _summary_bytes_used;

    static private CIntegerField summaryBytesUsedField;

    // G1MonitoringSupport* _g1mm;

    static private AddressField g1mmField;

    static private long oldSetFieldOffset;

    static private long humongousSetFieldOffset;

    static {

        VM.registerVMInitializedObserver(new Observer() {

                public void update(Observable o, Object data) {

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

                }

            });

    }

    static private synchronized void initialize(TypeDataBase db) {

        Type type = db.lookupType("G1CollectedHeap");

        hrsFieldOffset = type.getField("_hrs").getOffset();

        g1CommittedFieldOffset = type.getField("_g1_committed").getOffset();

        summaryBytesUsedField = type.getCIntegerField("_summary_bytes_used");

        g1mmField = type.getAddressField("_g1mm");

        oldSetFieldOffset = type.getField("_old_set").getOffset();

        humongousSetFieldOffset = type.getField("_humongous_set").getOffset();

    }

    public long capacity() {

        Address g1CommittedAddr = addr.addOffsetTo(g1CommittedFieldOffset);

        MemRegion g1Committed = new MemRegion(g1CommittedAddr);

        return g1Committed.byteSize();

    }

    public long used() {

        return summaryBytesUsedField.getValue(addr);

    }

    public long n_regions() {

        return hrs().length();

    }

    private HeapRegionSeq hrs() {

        Address hrsAddr = addr.addOffsetTo(hrsFieldOffset);

        return (HeapRegionSeq) VMObjectFactory.newObject(HeapRegionSeq.class,

                                                         hrsAddr);

    }

    public G1MonitoringSupport g1mm() {

        Address g1mmAddr = g1mmField.getValue(addr);

        return (G1MonitoringSupport) VMObjectFactory.newObject(G1MonitoringSupport.class, g1mmAddr);

    }

    public HeapRegionSetBase oldSet() {

        Address oldSetAddr = addr.addOffsetTo(oldSetFieldOffset);

        return (HeapRegionSetBase) VMObjectFactory.newObject(HeapRegionSetBase.class,

                                                             oldSetAddr);

    }

    public HeapRegionSetBase humongousSet() {

        Address humongousSetAddr = addr.addOffsetTo(humongousSetFieldOffset);

        return (HeapRegionSetBase) VMObjectFactory.newObject(HeapRegionSetBase.class,

                                                             humongousSetAddr);

    }

    private Iterator<HeapRegion> heapRegionIterator() {

        return hrs().heapRegionIterator();

    }

    public void heapRegionIterate(SpaceClosure scl) {

        Iterator<HeapRegion> iter = heapRegionIterator();

        while (iter.hasNext()) {

            HeapRegion hr = iter.next();

            scl.doSpace(hr);

        }

    }

    public CollectedHeapName kind() {

        return CollectedHeapName.G1_COLLECTED_HEAP;

    }

    public G1CollectedHeap(Address addr) {

        super(addr);

    }

}