@Test public void testSystemIndex() { IString test1 = new IString("AnIString1"); IString test2 = new IString("AnotherIString2"); IString test3 = new IString("YetAnotherIString2"); assertTrue(test1.id == Vocabulary.systemIndexOf(test1.toString())); assertTrue(test2.id == Vocabulary.systemIndexOf(test2.toString())); assertTrue(test3.id == Vocabulary.systemIndexOf(test3.toString())); }