*/
public void testAdd() {
TimePeriodValues tpv = new TimePeriodValues("Test");
MySeriesChangeListener listener = new MySeriesChangeListener();
tpv.addChangeListener(listener);
tpv.add(new TimePeriodValue(new SimpleTimePeriod(new Date(1L),
new Date(3L)), 99.0));
assertEquals(99.0, tpv.getValue(0).doubleValue(), EPSILON);
assertEquals(tpv, listener.getLastEvent().getSource());
// a null item should throw an IllegalArgumentException