/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, 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.function;
import org.geotools.filter.Expression;
import org.geotools.filter.FunctionExpressionImpl;
import org.opengis.filter.expression.Literal;
public class ClassifyFunction extends FunctionExpressionImpl {
//parameters are expression, classifier
public ClassifyFunction() {
super("classify");
}
public int getArgCount() {
return 2;
}
public Classifier getClassifier(Object context) {
Expression expr = (Expression) getParameters().get(1);
if (expr instanceof Literal) {
// this is not good practice! (but the other method doesn't work)
Literal literal = (Literal) expr;
return (Classifier) literal.getValue();
}
return (Classifier) expr.evaluate(context, Classifier.class);
}
public Expression getExpression() {
return (Expression) getParameters().get(0);
}
public Object evaluate(Object feature) {
Classifier classifier = getClassifier( feature );
Expression expression = getExpression();
return new Integer(classifier.classify(expression, feature));
}
}