Assert.assertNull(mm.getDataset(model3.getId()));
Assert.assertEquals(2, mm.numDatasets());
Assert.assertSame(model1, mm.getDataset(model1.getId()));
Assert.assertSame(model2, mm.getDataset(model2.getId()));
mm.clear();
Assert.assertNull(mm.getLastDataset());
Assert.assertNull(mm.getDataset(model3.getId()));
Assert.assertNull(mm.getDataset(model2.getId()));
Assert.assertNull(mm.getDataset(model1.getId()));
Assert.assertEquals(0, mm.numDatasets());