Application: gvSIG desktop

package org.gvsig.expressionevaluator.impl.function.spatial;

import org.apache.commons.lang3.Range;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.spi.AbstractFunction;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.aggregate.Aggregate;

import org.gvsig.fmap.geom.primitive.Primitive;

public class STGeometryNFunction extends AbstractFunction {

    public STGeometryNFunction() {

        super("OGC", "ST_GeometryN", Range.is(2));

    }

    @Override

    public boolean allowConstantFolding() {

        return true;

    }

    @Override

    public Object call(Interpreter interpreter, Object[] args) throws Exception {

        Geometry geom = getGeom(args, 0);

        if( geom instanceof Aggregate ) {

            Primitive r = ((Aggregate) geom).getPrimitiveAt(getInt(args, 1));

            return r;

        }

       return null;

    }

}