public void testSerialization() {
        PeriodAxisLabelInfo info1 = new PeriodAxisLabelInfo(
            Day.class, new SimpleDateFormat("d")
        );
        PeriodAxisLabelInfo info2 = null;
        try {
            ByteArrayOutputStream buffer = new ByteArrayOutputStream();
            ObjectOutput out = new ObjectOutputStream(buffer);
            out.writeObject(info1);
            out.close();

            ObjectInput in = new ObjectInputStream(
                new ByteArrayInputStream(buffer.toByteArray())
            );
            info2 = (PeriodAxisLabelInfo) in.readObject();
            in.close();
        }
        catch (Exception e) {
            System.out.println(e.toString());
        }
        boolean b = info1.equals(info2);
        assertTrue(b);