@Test
public void testCompareTo() {

  final EName a1 = new EName("http://localhost/a", "a");
  final EName b1 = new EName("http://localhost/b", "b");
  final EName a2 = new EName("", "a");
  final EName b2 = new EName("", "b");
  List<EName> eNames = new ArrayList<>();
  eNames.add(b1);
  eNames.add(a1);
  eNames.add(b2);
  eNames.add(a2);
  Collections.sort(eNames);
  assertEquals(a2, eNames.get(0));
  assertEquals(b2, eNames.get(1));
  assertEquals(a1, eNames.get(2));
  assertEquals(b1, eNames.get(3));
}