### Question:
DbNodeServiceImpl extends AbstractBaseService<DbNodeEntity> implements CacheUpdateService, DbNodeService, TimerService, PortalTimerService { @PreDestroy @Override public void stop() { isRunning = false; }  @Override void start(); @Override void updateCache(); @Override void checkDataSource(DbNodeEntity dbNodeEntity); @Override boolean hasSlave(DbNodeEntity dbNodeEntity); @Override void createDataSource(DbNodeEntity t1); void initDataSource(DbNodeEntity t1, String key, Map<String, DataSource> dataMap, boolean isMaster,
							   Transaction transaction); @Override Map<Long, DbNodeEntity> getCache(); @Override Map<String, List<DbNodeEntity>> getCacheByIp(); @Override void forceUpdateCache(); @PreDestroy @Override void stop(); @Override DataSource getDataSource(long id, boolean isMaster); @Override String info(); @Override Map<String, DataSource> getDataSource(); @Override void startPortal(); @Override void stopPortal(); @Override String getCacheJson();  }### Answer:
@Test public void stopTest() { dbNodeServiceImpl.stop(); assertEquals(false, dbNodeServiceImpl.isRunning); }