### Question:
CPF { public boolean isValido() { return new CPFValidator().invalidMessagesFor(numero).isEmpty(); } CPF(String numero); String getNumero(); String getNumeroFormatado(); boolean isValido(); @Override String toString(); @Override int hashCode(); @Override boolean equals(Object obj);  }### Answer:
@Test public void shouldReturnIfIsValid() throws Exception { CPF cpfValido = new CPF("111.444.777-35"); CPF cpfInvalido = new CPF("843.843.131-85"); assertTrue(cpfValido.isValido()); assertFalse(cpfInvalido.isValido()); }