/*
* $Id$
*
* Copyright (C) 2003-2014 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.def;
import org.jnode.vm.VmMagic;
import org.jnode.annotation.MagicPermission;
import org.jnode.vm.classmgr.ObjectFlags;
import org.jnode.vm.classmgr.VmClassType;
import org.jnode.vm.facade.ObjectVisitor;
import org.jnode.vm.memmgr.HeapHelper;
import org.vmmagic.pragma.Uninterruptible;
/**
* @author Ewout Prangsma (epr@users.sourceforge.net)
*/
@MagicPermission
final class GCSweepVisitor extends ObjectVisitor implements ObjectFlags,
Uninterruptible {
private final HeapHelper helper;
/**
* The heap that is currently being visited
*/
private VmDefaultHeap currentHeap;
public GCSweepVisitor(DefaultHeapManager heapMgr) {
this.helper = heapMgr.getHelper();
}
/**
* Mark every visited object white.
*
* @param object
* @return boolean
*/
public final boolean visit(Object object) {
final int gcColor = VmMagic.getObjectColor(object);
if (gcColor == GC_WHITE) {
final boolean finalized = VmMagic.isFinalized(object);
if (finalized) {
// Already finalized, we can free it now
currentHeap.free(object);
} else {
final VmClassType vmClass = VmMagic.getObjectType(object);
if (!vmClass.hasFinalizer()) {
// No finalizer, we can free it now
currentHeap.free(object);
} else {
// Mark object for invoke of finalizer on other thread.
helper.atomicChangeObjectColor(object, gcColor, GC_YELLOW);
}
}
} else if (gcColor != GC_YELLOW) {
helper.atomicChangeObjectColor(object, gcColor, GC_WHITE);
}
return true;
}
/**
* @return Returns the currentHeap.
*/
public final VmDefaultHeap getCurrentHeap() {
return this.currentHeap;
}
/**
* @param currentHeap The currentHeap to set.
*/
public final void setCurrentHeap(VmDefaultHeap currentHeap) {
this.currentHeap = currentHeap;
}
}