Strange Age output using Joda time?

[Jacky Luk]

 public void updateAge() throws ParseException
    {
        // String to Date
        SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");
        java.sql.Date d = new java.sql.Date(format.parse(
                          jFormattedDOB.getText().trim()).getTime());
        
        GregorianCalendar gc = new GregorianCalendar();
        gc.setTime(d);
        DateMidnight birthdate = new DateMidnight(gc.get(Calendar.YEAR),
                   gc.get(Calendar.MONTH), gc.get(Calendar.DAY_OF_MONTH));
        
        DateTime now = new DateTime();
        Years age = Years.yearsBetween(birthdate, now);
        System.out.println("Age = " + age.toString());
        jTextAge.setText(age.toString());
        
    }

I've got
Age = P20Y
What do the 'P' and 'Y' stand for?
Thanks
Jack

[Jacky Luk]

Jack Luk wrote:

 public void updateAge() throws ParseException
    {
        // String to Date
        SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");
        java.sql.Date d = new java.sql.Date(format.parse(
                          jFormattedDOB.getText().trim()).getTime());
        
        GregorianCalendar gc = new GregorianCalendar();
        gc.setTime(d);
        DateMidnight birthdate = new DateMidnight(gc.get(Calendar.YEAR),
                   gc.get(Calendar.MONTH), gc.get(Calendar.DAY_OF_MONTH));
        
        DateTime now = new DateTime();
        Years age = Years.yearsBetween(birthdate, now);
        System.out.println("Age = " + age.toString());
        jTextAge.setText(age.toString());
        
    }

I've got
Age = P20Y
What do the 'P' and 'Y' stand for?
Thanks
Jack

Sorry, I know now year.getYear()

[Jesper de Jong]

The API documentation of org.joda.time.Years.toString() answers your question: it returns the period as a string in ISO 8601 format, a standard format for representing dates, times, periods, etc.

"P20Y" in this format means a period of 20 years.

[Stephen Colebourne]

Please use LocalDate, not DateMidnight. DateMidnight does not work well in some countries where midnight does not exist once a year due to daylight savings.

In addition, LocalDate has dedicated methods fromDateFields() and fromCalendarFields() to convert from java.util.Date and Calendar.