/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2006-2008, Open Source Geospatial Foundation (OSGeo)
*
* 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;
* version 2.1 of the License.
*
* 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.
*/
package org.geotools.filter.visitor;
import org.opengis.filter.expression.Add;
import org.opengis.filter.expression.Divide;
import org.opengis.filter.expression.ExpressionVisitor;
import org.opengis.filter.expression.Function;
import org.opengis.filter.expression.Literal;
import org.opengis.filter.expression.Multiply;
import org.opengis.filter.expression.NilExpression;
import org.opengis.filter.expression.PropertyName;
import org.opengis.filter.expression.Subtract;
/**
* This class does *nothing* - useful to prevent null checks in AbstractFilterVisitor.
*
* @author Jody
*
* @source $URL$
*/
public class NullExpressionVisitor implements ExpressionVisitor{
public Object visit( NilExpression expression, Object extraData ) {
return null;
}
public Object visit( Add expression, Object extraData ) {
return null;
}
public Object visit( Divide expression, Object extraData ) {
return null;
}
public Object visit( Function expression, Object extraData ) {
return null;
}
public Object visit( Literal expression, Object extraData ) {
return null;
}
public Object visit( Multiply expression, Object extraData ) {
return null;
}
public Object visit( PropertyName expression, Object extraData ) {
return null;
}
public Object visit( Subtract expression, Object extraData ) {
return null;
}
}