### Question:
SxpEpProviderProviderInstance implements SxpEpProviderProvider, ClusterSingletonService, AutoCloseable { @Override public ServiceGroupIdentifier getIdentifier() { return IDENTIFIER; } SxpEpProviderProviderInstance(DataBroker dataBroker, BaseEndpointService endpointService,
                                         DomainSpecificRegistry registry,
                                         ClusterSingletonServiceProvider clusterSingletonService,
                                         SgtGeneratorConfig sgtGeneratorConfig); void initialize(); @Override void instantiateServiceInstance(); @Override ListenableFuture<Void> closeServiceInstance(); @Override void close(); @Override ServiceGroupIdentifier getIdentifier(); @Override EPToSgtMapper getEPToSgtMapper(); @Override EPPolicyTemplateProviderRegistry getEPPolicyTemplateProviderRegistry();  }### Answer:
@Test public void testGetIdentifier() throws Exception { final ServiceGroupIdentifier identifier = instance.getIdentifier(); Assert.assertEquals("gbp-service-group-identifier", identifier.getValue()); }