### Question:
Tracker implements IOFogModule { @Override public int getModuleIndex() { return Constants.TRACKER; }  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 getModuleIndex() { assertEquals(Constants.TRACKER, tracker.getModuleIndex()); }