I can't print GregorianCalendar

    package Tests;

import java.util.Date;
import java.util.GregorianCalendar;

public class Data 
{

    public static void main(String[] args) 
    {
        GregorianCalendar time = new GregorianCalendar(1999, 2, 2);
        System.out.println(time);
    }

}

I receive this

java.util.GregorianCalendar[time=?,areFieldsSet=false,areAllFieldsSet=false,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Europe/Belgrade",offset=3600000,dstSavings=3600000,useDaylight=true,transitions=119,lastRule=java.util.SimpleTimeZone[id=Europe/Belgrade,offset=3600000,dstSavings=3600000,useDaylight=true,startYear=0,startMode=2,startMonth=2,startDay=-1,startDayOfWeek=1,startTime=3600000,startTimeMode=2,endMode=2,endMonth=9,endDay=-1,endDayOfWeek=1,endTime=3600000,endTimeMode=2]],firstDayOfWeek=2,minimalDaysInFirstWeek=4,ERA=?,YEAR=1999,MONTH=2,WEEK_OF_YEAR=?,WEEK_OF_MONTH=?,DAY_OF_MONTH=2,DAY_OF_YEAR=?,DAY_OF_WEEK=?,DAY_OF_WEEK_IN_MONTH=?,AM_PM=0,HOUR=0,HOUR_OF_DAY=0,MINUTE=0,SECOND=0,MILLISECOND=?,ZONE_OFFSET=?,DST_OFFSET=?]

How I can print it?

---

you can use this like :-

GregorianCalendar calendar = new GregorianCalendar();
Date now = calendar.getTime();
System.out.println(now);

or

Calendar cal2 = new GregorianCalendar(2010, 9, 26);  // allocate with the specified date
cal2.get(Calendar.DAY_OF_WEEK);                      // 1 (Sunday) to 7 (Saturday)

---

when you call

System.out.println(time)

you've actually calling the toString() method of the Calendar instance (in this case, a GregorianCalendar one)

In order to have a properly formatted date, use SimpleDateFormat as stated in the Javadoc

https://docs.oracle.com/javase/tutorial/i18n/format/simpleDateFormat.html

---

java.time

The modern solution uses the LocalDate class instead. Avoid GregorianCalendar as it is now obsolete.

LocalDate ld = LocalDate.of( 1999 , Month.FEBRUARY , 2 ) ;

ld.toString(): 1999-02-02

The toString method uses the standard ISO 8601 formats. For other formats, use the DateTimeFormatter class. Search Stack Overflow for more examples and discussion, as that has beeen covered many many times.

Generally best to let DateTimeFormatter automatically localize for you.

Locale locale = Locale.CANADA_FRENCH ;
DateTimeFormatter f = DateTimeFormatter.ofLocalizedDate( FormatStyle.FULL ).withLocale( locale ) ;
String output = ld.format( f ) ;

mardi 2 février 1999

---

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date , Calendar , & SimpleDateFormat .

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

Where to obtain the java.time classes?

Java SE 8 , Java SE 9 , and later

Built-in.

Part of the standard Java API with a bundled implementation.

Java 9 adds some minor features and fixes.

Java SE 6 and Java SE 7

Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport .

Android

The ThreeTenABP project adapts ThreeTen-Backport (mentioned above) for Android specifically.

See How to use ThreeTenABP….

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval , YearWeek , YearQuarter , and more.

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