@Test
public void testGetMin() {

    Configuration config = new Configuration();
    config.setTimeRepresentation(TimeRepresentation.INTERVAL);
    GraphModelImpl graphModel = new GraphModelImpl(config);
    TimeStore timeStore = graphModel.store.timeStore;
    IntervalIndexStore store = (IntervalIndexStore) timeStore.nodeIndexStore;
    Assert.assertEquals(store.mainIndex.getMinTimestamp(), Double.NEGATIVE_INFINITY);
    store.add(new Interval(1.0, 3.0));
    Assert.assertEquals(store.mainIndex.getMinTimestamp(), 1.0);
    store.add(new Interval(2.0, 3.0));
    Assert.assertEquals(store.mainIndex.getMinTimestamp(), 1.0);
    store.remove(new Interval(1.0, 3.0));
    Assert.assertEquals(store.mainIndex.getMinTimestamp(), 2.0);
}