assertTrue(i.hasNext());
TestHelperSimple simpleHelper = (TestHelperSimple)i.next();
assertEquals(simpleHelper.getNumber(), 222l);
assertEquals(simpleHelper.getString(), "aaa");
assertTrue(i.hasNext());
TestHelperOther otherHelper = (TestHelperOther)i.next();
assertEquals(otherHelper.getNumber(), 123l);
assertEquals(otherHelper.getLetter(), "ccc");
} // end testAbstractObject()