### Question:
Tracker implements IOFogModule { public static Tracker getInstance() { if (instance == null) { synchronized (Tracker.class) { if (instance == null) instance = new Tracker(); } } return instance; }  static Tracker getInstance(); @Override void start(); @Override int getModuleIndex(); @Override String getModuleName(); void handleEvent(TrackingEventType type, String value); void handleEvent(TrackingEventType type, JsonStructure value);  }### Answer:
@Test public void testGetInstanceIsSameAsMock() { assertSame(tracker, Tracker.getInstance()); }