/* This file is part of the db4o object database http://www.db4o.com
Copyright (C) 2004 - 2011 Versant Corporation http://www.versant.com
db4o is free software; you can redistribute it and/or modify it under
the terms of version 3 of the GNU General Public License as published
by the Free Software Foundation.
db4o 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
for more details.
You should have received a copy of the GNU General Public License along
with this program. If not, see http://www.gnu.org/licenses/. */
package com.db4o.internal.delete;
import com.db4o.diagnostic.DefragmentRecommendation.*;
import com.db4o.internal.*;
import com.db4o.internal.diagnostic.*;
import com.db4o.internal.marshall.*;
import com.db4o.internal.slots.*;
import com.db4o.reflect.*;
import com.db4o.typehandlers.*;
/**
* @exclude
*/
public class DeleteContextImpl extends ObjectHeaderContext implements DeleteContext, ObjectIdContext {
private final ReflectClass _fieldClass;
private final Config4Field _fieldConfig;
public DeleteContextImpl(StatefulBuffer buffer, ObjectHeader objectHeader, ReflectClass fieldClass, Config4Field fieldConfig){
super(buffer.transaction(), buffer, objectHeader);
_fieldClass = fieldClass;
_fieldConfig = fieldConfig;
}
public DeleteContextImpl(DeleteContextImpl parentContext, ReflectClass fieldClass, Config4Field fieldConfig){
this(parentContext.statefulBuffer(), parentContext._objectHeader, fieldClass, fieldConfig);
}
public void cascadeDeleteDepth(int depth) {
statefulBuffer().setCascadeDeletes(depth);
}
private StatefulBuffer statefulBuffer() {
return ((StatefulBuffer)buffer());
}
public int cascadeDeleteDepth() {
return statefulBuffer().cascadeDeletes();
}
public boolean cascadeDelete() {
return cascadeDeleteDepth() > 0;
}
public void defragmentRecommended() {
DiagnosticProcessor dp = container()._handlers.diagnosticProcessor();
if(dp.enabled()){
dp.defragmentRecommended(DefragmentRecommendationReason.DELETE_EMBEDED);
}
}
public Slot readSlot() {
return new Slot(buffer().readInt(), buffer().readInt());
}
public void delete(TypeHandler4 handler){
final TypeHandler4 correctHandlerVersion = HandlerRegistry.correctHandlerVersion(this, handler);
int preservedCascadeDepth = cascadeDeleteDepth();
cascadeDeleteDepth(adjustedDepth());
if(Handlers4.handleAsObject(correctHandlerVersion)){
deleteObject();
}else{
correctHandlerVersion.delete(DeleteContextImpl.this);
}
cascadeDeleteDepth(preservedCascadeDepth);
}
public void deleteObject() {
int id = buffer().readInt();
if(cascadeDelete()){
container().deleteByID(transaction(), id, cascadeDeleteDepth());
}
}
private int adjustedDepth(){
if(Platform4.isStruct(_fieldClass)){
return 1;
}
if(_fieldConfig == null){
return cascadeDeleteDepth();
}
if(_fieldConfig.cascadeOnDelete().definiteYes()){
return 1;
}
if(_fieldConfig.cascadeOnDelete().definiteNo()){
return 0;
}
return cascadeDeleteDepth();
}
public int objectId() {
return statefulBuffer().getID();
}
}