@Test
public void should_classify_instance_without_classifier() {

	// Given
	String classifierName = "TestLearner";
	ClassifyQuery<Boolean> query = new ClassifyQuery<Boolean>(classifierName);
	double[] features1 = new double[10];
	double[] features2 = new double[10];
	TridentTuple tuple1 = createMockedInstanceTuple(features1);
	TridentTuple tuple2 = createMockedInstanceTuple(features2);
	List<TridentTuple> tuples = Arrays.asList(tuple1, tuple2);
	MapState<Classifier<Boolean>> state = mock(MapState.class);
	given(state.multiGet(asList(asList((Object) classifierName)))).willReturn(EMPTY_LIST);
	// When
	List<Boolean> labels = query.batchRetrieve(state, tuples);
	assertEquals(2, labels.size());
	assertNull(labels.get(0));
	assertNull(labels.get(1));
}