/*

 * $Id$

 *

 * Copyright (C) 2003-2009 JNode.org

 *

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

 * under the terms of the GNU Lesser General Public License as published

 * by the Free Software Foundation; either version 2.1 of the License, or

 * (at your option) any later version.

 *

 * This library 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 Lesser General Public 

 * License for more details.

 *

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

 * along with this library; If not, write to the Free Software Foundation, Inc., 

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

 */

package org.jnode.vm.memmgr.generational;

import org.jnode.annotation.Inline;

import org.jnode.annotation.MagicPermission;

import org.jnode.vm.VmMagic;

import org.jnode.vm.classmgr.ObjectFlags;

import org.jnode.vm.classmgr.VmClassType;

import org.jnode.vm.classmgr.VmMethod;

import org.jnode.vm.memmgr.HeapHelper;

/**

 * @author Loic Rouchon (loic.rouchon@insa-lyon.fr)

 */

@MagicPermission

final class GenGCYellowObjectManager {

    private final HeapHelper heapHelper;

    private VmDefaultHeap currentHeap;

    private long nbYellowObjects = 0L;

    private GenGCStatistics stats;

    public GenGCYellowObjectManager(HeapHelper heapHelper) {

        this.heapHelper = heapHelper;

    }

    @Inline

    public final void markObjectAsYellow(Object object) {

        heapHelper.atomicChangeObjectColor(object, ObjectFlags.GC_WHITE, ObjectFlags.GC_YELLOW);

        nbYellowObjects++;

        syncStats();

    }

    @Inline

    public final void deleteObject(Object object) {

        nbYellowObjects--;

        finalizeObject(object);

        currentHeap.free(object);

        syncStats();

    }

    @Inline

    public final boolean areObjectsYellow() {

        return nbYellowObjects > 0L;

    }

    @Inline

    private void syncStats() {

        stats.nbYellowObjects = nbYellowObjects;

    }

    /**

     * @param currentHeap

     *            The currentHeap to set.

     */

    public final void setCurrentHeap(VmDefaultHeap currentHeap) {

        this.currentHeap = currentHeap;

    }

    /**

     * Checks if the object needs to be finalized and if yes, do it

     * 

     * @param objectToFinalize

     *            the object to finalize

     */

    @Inline

    private void finalizeObject(Object objectToFinalize) {

        if (!VmMagic.isFinalized(objectToFinalize)) {

            final VmClassType<?> vmClass = VmMagic.getObjectType(objectToFinalize);

            if (vmClass.hasFinalizer()) {

                doFinalize(objectToFinalize, vmClass);

            }

        }

    }

    /**

     * Finalizes the given object of type <code>vmClass</code>

     * 

     * @param objectToFinalize

     *            the object to finalize

     * @param vmClass

     *            the vmClass corresponding to the object class

     */

    @Inline

    private void doFinalize(Object objectToFinalize, VmClassType<?> vmClass) {

        final VmMethod finalizeMethod = vmClass.getFinalizeMethod();

        try {

            heapHelper.invokeFinalizer(finalizeMethod, objectToFinalize);

        } catch (Throwable ex) {

            // Ignore error in finalize

        }

        heapHelper.setFinalized(objectToFinalize);

    }

    public void setStats(GenGCStatistics stats) {

        this.stats = stats;

    }

}