### Question:
AletheiaStreams { public KafkaStreams constructStreamsInstance() { if (!originalConfig.containsKey(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG)) { effectiveConfig.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, getBootstrapServers()); } effectiveConfig.putAll(originalConfig); return new KafkaStreams(kstreamBuilder, new StreamsConfig(effectiveConfig)); } AletheiaStreams(final Map<String, Object> streamsAppConfig); KStream<String, TDomainClass> stream(final AletheiaConfig config,
                                                             final Class<TDomainClass> domainClass,
                                                             final String consumeFromEndPointId,
                                                             final String datumSerDeId); KStream<String, TDomainClass> stream(final AletheiaConfig config,
                                                             final Class<TDomainClass> domainClass,
                                                             final String consumeFromEndPointId,
                                                             final String datumSerDeId,
                                                             final SerDeListener<TDomainClass> serDeListener); KStream<String, DatumEnvelope> envelopeStream(final AletheiaConfig config,
                                                       final String consumeFromEndPointId); KafkaStreams constructStreamsInstance(); KStreamBuilder getKStreamBuilder(); Map<String, Object> getEffectiveConfig();  }### Answer:
@Test public void whenNoStreamCreatedShouldThrow() throws Exception { expectedException.expect(IllegalStateException.class); final AletheiaStreams aletheiaStreams = new AletheiaStreams(emptyAppConfig); aletheiaStreams.constructStreamsInstance(); }