@Test
public void tryToCreateInstanceWithInvalidSubject() {

    final String invalidSubject = "§foo";
    assertThatExceptionOfType(DittoHeaderInvalidException.class)
            .isThrownBy(() -> MessageHeadersBuilder.newInstance(DIRECTION, THING_ID, invalidSubject))
            .withMessageContaining(invalidSubject)
            .withMessageEndingWith("is not a valid message subject.")
            .withNoCause();
}