### Question:
StatsManager { public static StatsManager getInstance() { return InstanceHolder.instance; } private  StatsManager(); static StatsManager getInstance(); static List<String> getComponentNames(); static OperationStats getComponent(String component); synchronized void stop(); synchronized void resume(); synchronized boolean isRunning(); synchronized Object takeSnapshot(); @SuppressWarnings("unused") synchronized void mergeWithSnapshot(Object snapshot); @SuppressWarnings("unused") synchronized void startFromSnapshot(Object snapshot); String printStats();  }### Answer:
@Test public void testGetInstance() { StatsManager service = StatsManager.getInstance(); assertNotNull(service); assertTrue(service.isRunning()); }