Assert.assertFalse(c1.isDefiniteClause());
c1.addNegativeLiteral(new Predicate("Pred1", new ArrayList<Term>()));
Assert.assertFalse(c1.isDefiniteClause());
c1.addPositiveLiteral(new Predicate("Pred2", new ArrayList<Term>()));
Assert.assertTrue(c1.isDefiniteClause());
c1.addNegativeLiteral(new Predicate("Pred3", new ArrayList<Term>()));
Assert.assertTrue(c1.isDefiniteClause());
c1.addNegativeLiteral(new Predicate("Pred4", new ArrayList<Term>()));