### Question:
AnnotationMirrors { public static AnnotationValue getAnnotationValue( AnnotationMirror annotationMirror, String elementName) { return getAnnotationElementAndValue(annotationMirror, elementName).getValue(); } private  AnnotationMirrors(); static Equivalence<AnnotationMirror> equivalence(); static ImmutableMap<ExecutableElement, AnnotationValue> getAnnotationValuesWithDefaults(
      AnnotationMirror annotation); static AnnotationValue getAnnotationValue(
      AnnotationMirror annotationMirror, String elementName); static Map.Entry<ExecutableElement, AnnotationValue> getAnnotationElementAndValue(
      AnnotationMirror annotationMirror, final String elementName); static ImmutableSet<? extends AnnotationMirror> getAnnotatedAnnotations(Element element,
      final Class<? extends Annotation> annotationType);  }### Answer:
@Test public void testGetValueEntryFailure() { try { AnnotationMirrors.getAnnotationValue(annotationOn(TestClassBlah.class), "a"); } catch (IllegalArgumentException e) { assertThat(e) .hasMessageThat() .isEqualTo( "@com.google.auto.common.AnnotationMirrorsTest.Outer does not define an element a()"); return; } fail("Should have thrown."); }