private void createGeometrySLD( Color colour, String geomXPath, SLDContentManager sldContentManager ) throws IllegalFilterException {
// create Point rule.
Rule rule=sldContentManager.getDefaultRule();
PropertyIsEqualTo filter = createGeometryFunctionFilter(geomXPath, Point.class.getSimpleName());
rule.setFilter(filter);
rule.symbolizers().add(createPointSymbolizer(colour));
sldContentManager.getDefaultFeatureTypeStyle().rules().add(rule);
// create MultiPoint rule
rule=sldContentManager.createRule();
filter = createGeometryFunctionFilter(geomXPath, MultiPoint.class.getSimpleName());