public final boolean checkIfExecuted(String input) {
    return this.validator.isExecuted(Optional.of(ByteString.copyFromUtf8(input)));
  }
@Test
  public void checkIfExecuted_withString_executesValidator() {
    TestValidatorIsCalledValidator testValidator = new TestValidatorIsCalledValidator();
    Payload payload = new Payload("my-payload", testValidator, PAYLOAD_ATTRIBUTES, CONFIG);

    payload.checkIfExecuted("my-input");
    assertTrue(testValidator.wasCalled);
  }