mm.addDataset(model2);
Assert.assertEquals(model2.getId(), mm.getLastDataset().getId());
Assert.assertEquals(2, mm.numDatasets());
Assert.assertEquals(2, mm.getDatasets().size());
mm.addDataset(model3);
Assert.assertEquals(model3.getId(), mm.getLastDataset().getId());
Assert.assertEquals(3, mm.numDatasets());
Assert.assertEquals(3, mm.getDatasets().size());
Assert.assertSame(model1, mm.getDataset(model1.getId()));