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Trieda Java Calendar je abstraktná trieda, ktorá poskytuje metódy na prevod dátumu medzi konkrétnym časovým okamihom a množinou polí kalendára, ako je MESIAC, ROK, HODINA atď. Zdedí triedu Object a implementuje rozhranie Comparable.

Deklarácia triedy Java Calendar

Pozrime sa na deklaráciu triedy java.util.Calendar.

 public abstract class Calendar extends Object implements Serializable, Cloneable, Comparable 

Zoznam metód kalendára

Príklad triedy kalendára Java

 import java.util.Calendar; public class CalendarExample1 { public static void main(String[] args) { Calendar calendar = Calendar.getInstance(); System.out.println('The current date is : ' + calendar.getTime()); calendar.add(Calendar.DATE, -15); System.out.println('15 days ago: ' + calendar.getTime()); calendar.add(Calendar.MONTH, 4); System.out.println('4 months later: ' + calendar.getTime()); calendar.add(Calendar.YEAR, 2); System.out.println('2 years later: ' + calendar.getTime()); } } 

Výkon:

 The current date is : Thu Jan 19 18:47:02 IST 2017 15 days ago: Wed Jan 04 18:47:02 IST 2017 4 months later: Thu May 04 18:47:02 IST 2017 2 years later: Sat May 04 18:47:02 IST 2019 

Príklad triedy Java Calendar: get()

 import java.util.*; public class CalendarExample2{ public static void main(String[] args) { Calendar calendar = Calendar.getInstance(); System.out.println('At present Calendar's Year: ' + calendar.get(Calendar.YEAR)); System.out.println('At present Calendar's Day: ' + calendar.get(Calendar.DATE)); } } 

Výkon:

 At present Calendar's Year: 2017 At present Calendar's Day: 20 

Príklad triedy Java Calendar: getInstance()

 import java.util.*; public class CalendarExample3{ public static void main(String[] args) { Calendar calendar = Calendar.getInstance(); System.out.print('At present Date And Time Is: ' + calendar.getTime()); } } 

Výkon:

 At present Date And Time Is: Fri Jan 20 14:26:19 IST 2017 

Príklad triedy kalendára Java: getMaximum()

 import java.util.*; public class CalendarExample4 { public static void main(String[] args) { Calendar calendar = Calendar.getInstance(); int maximum = calendar.getMaximum(Calendar.DAY_OF_WEEK); System.out.println('Maximum number of days in week: ' + maximum); maximum = calendar.getMaximum(Calendar.WEEK_OF_YEAR); System.out.println('Maximum number of weeks in year: ' + maximum); } } 

Výkon:

 Maximum number of days in week: 7 Maximum number of weeks in year: 53 

Príklad triedy kalendára Java: getMinimum()

 import java.util.*; public class CalendarExample5 { public static void main(String[] args) { Calendar cal = Calendar.getInstance(); int maximum = cal.getMinimum(Calendar.DAY_OF_WEEK); System.out.println('Minimum number of days in week: ' + maximum); maximum = cal.getMinimum(Calendar.WEEK_OF_YEAR); System.out.println('Minimum number of weeks in year: ' + maximum); } } 

Výkon:

 Minimum number of days in week: 1 Minimum number of weeks in year: 1