@Test
  public void other_types_are_not_valid() throws Exception {

    boolean intValidation = SType.TEXT.validate(54);
    assertThat(intValidation).isFalse();

    boolean doubleValidation = SType.TEXT.validate(53.2d);
    assertThat(doubleValidation).isFalse();

    boolean booleanValidation = SType.TEXT.validate(true);
    assertThat(booleanValidation).isFalse();
  }
  @Test
  public void character_are_valid() throws Exception {

    boolean validation = SType.TEXT.validate('a');

    assertThat(validation).isTrue();
  }
  @Test
  public void null_is_valid() throws Exception {

    boolean validation = SType.TEXT.validate(null);

    assertThat(validation).isTrue();
  }
  @Test
  public void string_are_valid() throws Exception {

    boolean validation = SType.TEXT.validate("this is a String");

    assertThat(validation).isTrue();
  }