Java 8 – How to get Number of Days in a Month from LocalDate ?

July 31, 2022 SJ Java 8, Java 8 Date/Time 0

In this article, we will learn how to get number of Days in a Month from LocalDate and Calendar

1. Get Number of Days in a Month from LocalDate :

  • Sometimes, we need Number of Days in a Month from current LocalDate for some business requirement
  • To get number of days in a Month from LocalDate, we can use below method
    • lengthOfMonth() – returns Number of Days in a Year from invoking LocalDate
  • Finally, print number of days in a month to the console

1.1 Get number of Days for Feb-2016 & Feb-2022

  • In the below illustration, we will form LocalDate for February–2016 and February–2022 assigning,
    • Day of Month as 1
  • Note:- Number of days for every month is fixed except for February which increases by a Day in a Leap Year

GetLengthOfMonthFromLocalDate2.java

package in.bench.resources.java8.localdate.examples;

import java.time.LocalDate;
import java.time.Month;

public class GetLengthOfMonthFromLocalDate2 {

	public static void main(String[] args) {

		// 1.  form LocalDate for February-2022
		LocalDate localDate = LocalDate.of(2022, Month.FEBRUARY, 1);
		System.out.println("LocalDate is = " + localDate);


		// 1.1 Number of days in Feb-2022
		System.out.println("Number of Days in " 
				+ localDate.getMonth() + "-" 
				+ localDate.getYear() + " is = \t" 
				+ localDate.lengthOfMonth());



		// 2.  form LocalDate for February-2016
		LocalDate localDate2 = LocalDate.of(2016, Month.FEBRUARY, 1);
		System.out.println("\nLocalDate is = " + localDate2);


		// 2.1 Number of days in Feb-2016
		System.out.print("Number of Days in " 
				+ localDate2.getMonth() + "-" 
				+ localDate2.getYear() + " is = \t" 
				+ localDate2.lengthOfMonth());
	}
}

Output:

LocalDate is = 2022-02-01
Number of Days in FEBRUARY-2022 is = 	28

LocalDate is = 2016-02-01
Number of Days in FEBRUARY-2016 is = 	29

1.2 Get number of Days for each Month of Year-2022

  • In the below illustration, we will form LocalDate for all 12 months starting from January to December assigning,
    • Day of Month as 1
    • Year as 2022

GetLengthOfMonthFromLocalDate.java

package in.bench.resources.java8.localdate.examples;

import java.time.LocalDate;
import java.util.Arrays;
import java.util.List;

public class GetLengthOfMonthFromLocalDate {

	public static void main(String[] args) {

		// 1. form LocalDate from January to December and add to List
		List<LocalDate> localDates = Arrays.asList(
				LocalDate.of(2022, 1, 1),
				LocalDate.of(2022, 2, 1),
				LocalDate.of(2022, 3, 1),
				LocalDate.of(2022, 4, 1),
				LocalDate.of(2022, 5, 1),
				LocalDate.of(2022, 6, 1),
				LocalDate.of(2022, 7, 1),
				LocalDate.of(2022, 8, 1),
				LocalDate.of(2022, 9, 1),
				LocalDate.of(2022, 10, 1),
				LocalDate.of(2022, 11, 1),
				LocalDate.of(2022, 12, 1)
				);


		// 2. LocalDate - get number of Days in each month
		System.out.print("Number of Days in each Month :- \n");
		localDates.forEach(localDate -> System.out.println("Number of Days in " 
				+ localDate.getMonth() + "-" 
				+ localDate.getYear() + " is = \t" 
				+ localDate.lengthOfMonth()));
	}
}

Output:

Number of Days in each Month :- 

Number of Days in JANUARY-2022 is = 	31
Number of Days in FEBRUARY-2022 is = 	28
Number of Days in MARCH-2022 is = 	31
Number of Days in APRIL-2022 is = 	30
Number of Days in MAY-2022 is = 	31
Number of Days in JUNE-2022 is = 	30
Number of Days in JULY-2022 is = 	31
Number of Days in AUGUST-2022 is = 	31
Number of Days in SEPTEMBER-2022 is = 	30
Number of Days in OCTOBER-2022 is = 	31
Number of Days in NOVEMBER-2022 is = 	30
Number of Days in DECEMBER-2022 is = 	31

2. Get Number of Days in a Month from Calendar/Date :

  • If the Java version used is lower than 8 then Calendar/Date classes can be used to get number of Days for any month of a year

2.1 Get number of Days for Feb-2016 & Feb-2022

  • Below illustration prints number of days for months of February–2016 and February–2022 with,
    • Day of Month field set to 1

GetLengthOfMonthFromCalendar2.java

package in.bench.resources.java8.localdate.examples;

import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.Locale;

public class GetLengthOfMonthFromCalendar2 {

	public static void main(String[] args) {


		// 1. Instantiate GregorianCalendar for February-2022
		Calendar calendar = new GregorianCalendar(2022, Calendar.FEBRUARY, 1);
		System.out.println("Date is = " + calendar.getTime());


		// 1.1 Number of days in Feb-2022
		System.out.println("Number of Days in " 
				+ calendar.getDisplayName(Calendar.MONTH, Calendar.LONG, Locale.ENGLISH) + "-" 
				+ calendar.get(Calendar.YEAR) + " is = \t" 
				+ calendar.getActualMaximum(Calendar.DAY_OF_MONTH));



		// 2. Instantiate GregorianCalendar for February-2016
		Calendar calendar2 = new GregorianCalendar(2016, Calendar.FEBRUARY, 1);
		System.out.println("\n\nDate is = " + calendar2.getTime());


		// 2.1 Number of days in Feb-2016
		System.out.print("Number of Days in " 
				+ calendar2.getDisplayName(Calendar.MONTH, Calendar.LONG, Locale.ENGLISH) + "-" 
				+ calendar2.get(Calendar.YEAR) + " is = \t" 
				+ calendar2.getActualMaximum(Calendar.DAY_OF_MONTH));
	}
}

Output:

Date is = Tue Feb 01 00:00:00 IST 2022
Number of Days in February-2022 is = 	28


Date is = Mon Feb 01 00:00:00 IST 2016
Number of Days in February-2016 is = 	29

2.2 Get number of Days for each Month of Year-2022

  • Below illustration prints number of days for each month of Year 2022 starting from January to December with,
    • Day of Month field set to 1

GetLengthOfMonthFromCalendar.java

package in.bench.resources.java8.localdate.examples;

import java.util.Arrays;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.List;
import java.util.Locale;

public class GetLengthOfMonthFromCalendar {

	public static void main(String[] args) {

		// 1. Instantiate GregorianCalendar from January to December and add to List
		List<Calendar> months = Arrays.asList(
				new GregorianCalendar(2022, Calendar.JANUARY, 1),
				new GregorianCalendar(2022, Calendar.FEBRUARY, 1),
				new GregorianCalendar(2022, Calendar.MARCH, 1),
				new GregorianCalendar(2022, Calendar.APRIL, 1),
				new GregorianCalendar(2022, Calendar.MAY, 1),
				new GregorianCalendar(2022, Calendar.JUNE, 1),
				new GregorianCalendar(2022, Calendar.JULY, 1),
				new GregorianCalendar(2022, Calendar.AUGUST, 1),
				new GregorianCalendar(2022, Calendar.SEPTEMBER, 1),
				new GregorianCalendar(2022, Calendar.OCTOBER, 1),
				new GregorianCalendar(2022, Calendar.NOVEMBER, 1),
				new GregorianCalendar(2022, Calendar.DECEMBER, 1)
				);


		// 2. Calendar - get number of Days in each month
		System.out.println("Number of Days in each Month :- \n");
		months.forEach(month -> System.out.println("Number of Days in " 
				+ month.getDisplayName(Calendar.MONTH, Calendar.LONG, Locale.ENGLISH) + "-" 
				+ month.get(Calendar.YEAR) + " is = \t" 
				+ month.getActualMaximum(Calendar.DAY_OF_MONTH)));
	}
}

Output:

Number of Days in each Month :- 

Number of Days in January-2022 is = 	31
Number of Days in February-2022 is = 	28
Number of Days in March-2022 is = 	31
Number of Days in April-2022 is = 	30
Number of Days in May-2022 is = 	31
Number of Days in June-2022 is = 	30
Number of Days in July-2022 is = 	31
Number of Days in August-2022 is = 	31
Number of Days in September-2022 is = 	30
Number of Days in October-2022 is = 	31
Number of Days in November-2022 is = 	30
Number of Days in December-2022 is = 	31

Related Articles:

References:

Happy Coding !!
Happy Learning !!

Java 8 – How to get Number of Days in a Year from LocalDate ?
Java 8 – How to alter Year, Month and Day fields of LocalDate ?

Related posts:

  1. Java 8 – How to get Date and Time fields from LocalDateTime ?
  2. Java 8 – How to get Year, Month and Day fields from LocalDate ?
  3. Java 8 – How to get Number of Days in a Year from LocalDate ?
  4. Java 8 – How to find difference between two OffsetDateTime using Period & Duration ?