### Question:
UniqueCheck extends AbstractAnnotationCheck<Unique> { @Override public Map<String, String> createMessageVariables() { Map<String, String> messageVariables = new HashMap<String, String>(); messageVariables.put("uk-context", uniqueKeyContext); return messageVariables; } UniqueCheck(); @Override void configure(Unique constraintAnnotation); @Override Map<String, String> createMessageVariables(); @Override boolean isSatisfied(Object validatedObject, Object value,
            OValContext context, Validator validator);  }### Answer:
@Test public void testCreateMessageVariables() { testee.configure(uniqueAnnotation); Map<String, String> messageVar = testee.createMessageVariables(); assertThat(messageVar).hasSize(1); assertThat(messageVar.get("uk-context")).isEqualTo(UK_CONTEXT); }