/**
* Returns a geometric object that represents the Point set union of two geometries.
*
* @param node1 xml element containing gml object(s)
* @param node2 xml element containing gml object(s)
* @return union geometry as a gml element
* @throws QueryException query exception
*/
@Deterministic
public ANode union(final ANode node1, final ANode node2) throws QueryException {
final Geometry geo1 = checkGeo(node1);
final Geometry geo2 = checkGeo(node2);
return gmlWriter(geo1.union(geo2));
}
