Why does a new SimpleDateFormat object contain calendar with the wrong year?

Question

I came upon a strange behavior that has left me curious and without a satisfactory explanation as yet.

For simplicity, I\'ve reduced the symptoms I\'ve noticed to th

Answer 1

SimpleDateFormat has mutable internal state. This is why I avoid it like the plague (I recommend Joda Time). This internal calendar is probably used during the process of parsing a date, but there's no reason it would be initialized to anything in particular before it has parsed a date.

Here's some code to illustrate:

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;

public class DateTest {
    public static void main(String[] args) {
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat();
        System.out.println("sdf cal: " + simpleDateFormat.getCalendar());
        System.out.println("new cal: " + new GregorianCalendar());
        System.out.println("new date: " + simpleDateFormat.format(new Date()));
        System.out.println("sdf cal: " + simpleDateFormat.getCalendar());
    }
}