assertNull(vis.lastLabel);
vis.lastLabel = null;
SampleResult res1 = SampleResult.createTestSample(29000, 30000);
res1.setSampleLabel("test1");
instance.sampleOccurred(new SampleEvent(res1, "tg"));
assertEquals("test1", vis.lastLabel);
vis.lastLabel = null;
SampleResult res2 = SampleResult.createTestSample(19000, 20000);
res2.setSampleLabel("test2");