### Question:
Samplers { public static SamplingResult emptySamplingResult(Decision decision) { switch (decision) { case RECORD_AND_SAMPLE: return EMPTY_RECORDED_AND_SAMPLED_SAMPLING_RESULT; case RECORD_ONLY: return EMPTY_RECORDED_SAMPLING_RESULT; case DROP: return EMPTY_NOT_SAMPLED_OR_RECORDED_SAMPLING_RESULT; } throw new AssertionError("unrecognised samplingResult"); } private  Samplers(); static SamplingResult samplingResult(Decision decision, Attributes attributes); static SamplingResult emptySamplingResult(Decision decision); static Sampler alwaysOn(); static Sampler alwaysOff(); static Sampler parentBased(Sampler root); static ParentBased.Builder parentBasedBuilder(Sampler root); static Sampler traceIdRatioBased(double ratio);  }### Answer:
@Test void emptySamplingDecision() { assertThat(Samplers.emptySamplingResult(Sampler.Decision.RECORD_AND_SAMPLE)) .isSameAs(Samplers.emptySamplingResult(Sampler.Decision.RECORD_AND_SAMPLE)); assertThat(Samplers.emptySamplingResult(Sampler.Decision.DROP)) .isSameAs(Samplers.emptySamplingResult(Sampler.Decision.DROP)); assertThat(Samplers.emptySamplingResult(Sampler.Decision.RECORD_AND_SAMPLE).getDecision()) .isEqualTo(Decision.RECORD_AND_SAMPLE); assertThat( Samplers.emptySamplingResult(Sampler.Decision.RECORD_AND_SAMPLE) .getAttributes() .isEmpty()) .isTrue(); assertThat(Samplers.emptySamplingResult(Sampler.Decision.DROP).getDecision()) .isEqualTo(Decision.DROP); assertThat(Samplers.emptySamplingResult(Sampler.Decision.DROP).getAttributes().isEmpty()) .isTrue(); }