### Question:
Kleene extends ERE { public static ERE get(ERE child) { return new Kleene(child); } private  Kleene(ERE child); static ERE get(ERE child); @Override EREType getEREType(); @Override String toString(); @Override ERE copy(); @Override boolean containsEpsilon(); @Override ERE derive(Symbol s);  }### Answer:
@Test public void testEquality() { ERE aStar_again = Kleene.get(a); assertEquals(aStar, aStar_again); assertEquals(0, aStar.compareTo(aStar_again)); }