public void testFormat_year() {
        DateTime dt = new DateTime(2004, 6, 9, 10, 20, 30, 40, UTC);
        DateTimeFormatter f = DateTimeFormat.forPattern("y").withLocale(Locale.UK);
        assertEquals(dt.toString(), "2004", f.print(dt));
        
        dt = dt.withZone(NEWYORK);
        assertEquals(dt.toString(), "2004", f.print(dt));
        
        dt = dt.withZone(TOKYO);
        assertEquals(dt.toString(), "2004", f.print(dt));
        
        dt = new DateTime(-123, 6, 9, 10, 20, 30, 40, UTC);
        assertEquals(dt.toString(), "-123", f.print(dt));

        // Added tests to ensure single sign digit parse fails properly
        try {
            f.parseDateTime("-");
            fail();
        } catch (IllegalArgumentException ex) {}

        try {
            f.parseDateTime("+");
            fail();
        } catch (IllegalArgumentException ex) {}
    }