@Test
public void invalidEntityTagsValue() {

    Mockito.when(headerDefinition.getJavaType()).thenReturn(EntityTagMatchers.class);
    final String value = "\"foo\",invalid\"bar\"";
    assertThatExceptionOfType(DittoHeaderInvalidException.class)
            .isThrownBy(() -> underTest.accept(headerDefinition, value))
            .withMessage("The value '%s' of the header '%s' is not a valid entity-tag.", "invalid\"bar\"",
                    HEADER_KEY)
            .withNoCause();
}