‘Using Java How to convert a date String to a Date or Calendar object?

DateFormat formatter = new SimpleDateFormat("MM/dd/yy");
try {
  Date date = formatter.parse("01/29/02");
} catch (ParseException e) {
  e.printStackTrace();
}
See SimpleDateFormat javadoc for more.
And to turn it into a Calendar, do:
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);