/*
* Copyright (c) 2006-2009 by Abacus Research AG, Switzerland.
* All rights reserved.
*
* This file is part of the Abacus Formula Compiler (AFC).
*
* For commercial licensing, please contact sales(at)formulacompiler.com.
*
* AFC is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* AFC 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 AFC. If not, see <http://www.gnu.org/licenses/>.
*/
package org.formulacompiler.compiler.internal.model.optimizer;
import org.formulacompiler.compiler.CallFrame;
import org.formulacompiler.compiler.internal.expressions.ExpressionNode;
import org.formulacompiler.compiler.internal.model.AbstractComputationModelVisitor;
import org.formulacompiler.compiler.internal.model.CellModel;
import org.formulacompiler.compiler.internal.model.ExpressionNodeForCellModel;
import org.formulacompiler.compiler.internal.model.ExpressionNodeForParentSectionModel;
public final class ReferenceCounter extends AbstractComputationModelVisitor
{
@Override
protected boolean visitCell( CellModel _cell )
{
if (_cell.isOutput()) {
reference( _cell, false );
}
return true;
}
void reference( CellModel _cell, boolean _makeSureIsCallable )
{
if (null == _cell) throw new IllegalArgumentException();
boolean notAnalyzedYet = (0 == _cell.getReferenceCount());
_cell.addReference();
if (_makeSureIsCallable) _cell.addReference();
if (notAnalyzedYet) {
addRefToEverythingReferencedBy( _cell.getExpression(), false );
addRefToEverythingReferencedBy( _cell.getCallChainToCall() );
}
}
void addRefToEverythingReferencedBy( ExpressionNode _expr, boolean _accessedBySubBand )
{
if (_expr == null) {
// nothing to do
}
else if (_expr instanceof ExpressionNodeForCellModel) {
ExpressionNodeForCellModel cellNode = (ExpressionNodeForCellModel) _expr;
CellModel cellModel = cellNode.getCellModel();
if (null != cellModel) {
reference( cellModel, _accessedBySubBand );
}
}
else {
final boolean argsBySubBand = _accessedBySubBand || (_expr instanceof ExpressionNodeForParentSectionModel);
for (ExpressionNode arg : _expr.arguments()) {
addRefToEverythingReferencedBy( arg, argsBySubBand );
}
}
}
private void addRefToEverythingReferencedBy( CallFrame _callChainToCall )
{
if (null == _callChainToCall) return;
for (Object arg : _callChainToCall.getArgs()) {
if (arg instanceof CellModel) {
CellModel cell = (CellModel) arg;
reference( cell, true );
}
}
addRefToEverythingReferencedBy( _callChainToCall.getPrev() );
}
}