// Get solid polygon(no hole)
LinearRing solidRing = GeometryUtil.gf().createLinearRing(
extRing.getCoordinates());
Polygon solidPg = GeometryUtil.gf().createPolygon(solidRing, null);
Geometry solidCutter = cutter.intersection(solidPg);
Geometry solidBounds = solidRing.difference(cutter);
Polygonizer pgzer = new Polygonizer();
for (int i = 0, count = solidBounds.getNumGeometries(); i < count; i++) {
pgzer.add(solidBounds.getGeometryN(i));
}