### Question:
ServiceCombServiceRegistry implements ServiceRegistry<ServiceCombRegistration> { @Override public void deregister(ServiceCombRegistration registration) { heartbeatScheduler.remove(); try { serviceCombClient .deRegisterInstance(RegisterCache.getServiceID(), RegisterCache.getInstanceID()); } catch (ServiceCombException e) { LOGGER.error("deRegisterInstance failed", e); } } ServiceCombServiceRegistry(ServiceCombClient serviceCombClient,
      HeartbeatScheduler heartbeatScheduler,
      ServiceCombDiscoveryProperties serviceCombDiscoveryProperties,
      ServiceCombWatcher serviceCombWatcher,
      TagsProperties tagsProperties); @Override void register(ServiceCombRegistration registration); @Override void deregister(ServiceCombRegistration registration); @Override void close(); @Override void setStatus(ServiceCombRegistration registration, String status); @Override String getStatus(ServiceCombRegistration registration); String getServiceID(); String getInstanceID();  }### Answer:
@Test public void deRegisterMicroservice() throws ServiceCombException { new Expectations() { { serviceCombClient.deRegisterInstance(anyString, anyString); result = true; } }; ServiceCombServiceRegistry serviceCombServiceRegistry = new ServiceCombServiceRegistry( serviceCombClient, heartbeatScheduler, serviceCombDiscoveryProperties, serviceCombWatcher, tagsProperties); serviceCombServiceRegistry.deregister(registration); }