### Question:
DummyFault extends Fault implements Validator, Controller, Interceptor { @Override public Set<Violation> validate() { System.out.printf("dummy-%s is valid\n", id()); return new HashSet<>(); }  @Override void activate(); @Override void deactivate(); @Override Set<Violation> validate(); @Override boolean apply(Invocation invocation);  }### Answer:
@Test public void testValidate() { assertTrue(new DummyFault().validate().isEmpty()); }