@Test
public void testGetRuleClass() {

  PlacementRule rule = PlacementFactory.getPlacementRule(
      DefaultPlacementRule.class, null);
  assertNotNull("Rule object is null", rule);
  // Should take anything as the second object: ignores unknown types in the
  // default implementation.
  rule = PlacementFactory.getPlacementRule(
      DefaultPlacementRule.class, "");
  assertNotNull("Rule object is null", rule);
}