### Question:
Epsilon extends ERE { @Override public String toString() { return "epsilon"; } private  Epsilon(); static Epsilon get(); @Override EREType getEREType(); @Override boolean equals(Object o); @Override int compareTo(Object o); @Override ERE copy(); @Override String toString(); @Override boolean containsEpsilon(); @Override ERE derive(Symbol s);  }### Answer:
@Test public void testString() { assertEquals("epsilon", epsilon.toString()); }