/*
* 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;
import org.opengis.filter.FilterVisitor;
import org.opengis.filter.expression.Expression;
public class IsNullImpl extends CompareFilterImpl implements
NullFilter {
public IsNullImpl(org.opengis.filter.FilterFactory factory, org.opengis.filter.expression.Expression expression) {
super( factory , expression , null );
filterType = FilterType.NULL;
}
public boolean evaluate(Object feature) {
Expression expr = getExpression();
Object value = eval(expr, feature);
return value == null;
}
public Object accept(FilterVisitor visitor, Object extraData) {
return visitor.visit( this, extraData );
}
public void nullCheckValue(org.geotools.filter.Expression nullCheck) throws IllegalFilterException {
setExpression( nullCheck );
}
public org.geotools.filter.Expression getNullCheckValue() {
return (org.geotools.filter.Expression) getExpression();
}
public Expression getExpression() {
return getExpression1();
}
public void setExpression(Expression expression) {
setExpression( expression );
}
}