@Before
 public void before() {
   when(configuration.getConfig(CorePlugin.class)).thenReturn(corePlugin);
   StageMonitor.reset();
   StageMonitor.setConfiguration(configuration);
   StageMonitor.setLogger(logger);
   assertFalse(StageMonitor.isStarted());
   assertTrue(StageMonitor.getMeasurementSession().isNull());
 }
 @After
 public void after() {
   StageMonitor.reset();
 }