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Java LocalDate Tutorial with Examples

1- LocalDate

The LocalDate class represents the local date in the ISO calendar system. It does not include time and time zone information. A LocalDate can be a date of birth, an official holiday, etc. it is related to a specific day of the year.

The LocalDate class is in the java.time package. Like other classes introduced in Java 8 Date Time API, LocalDate is immutable which means that all computations on LocalDate create a new LocalDate object, so it's safe to be used in multithreading environment.


public final class LocalDate
        implements Temporal, TemporalAdjuster, ChronoLocalDate, Serializable

2- Static Factory methods

The LocalDate class does not provide any constructor, but it provides static factory methods to create a new object.


static LocalDate now()
static LocalDate now(Clock clock)
static LocalDate now(ZoneId zone)
static LocalDate of(int year, int month, int dayOfMonth)
static LocalDate of(int year, Month month, int dayOfMonth)
static LocalDate ofEpochDay(long epochDay)
static LocalDate ofInstant(Instant instant, ZoneId zone)
static LocalDate ofYearDay(int year, int dayOfYear)
static LocalDate parse(CharSequence text)
static LocalDate parse(CharSequence text, DateTimeFormatter formatter)

Create a LocalDate object representing the current date from the system clock and default time zone (On your computer).


// Ex: Current date from the system clock in the default time-zone.
LocalDate localDate = LocalDate.now();
System.out.println("localDate.now(): " + localDate); // 2021-06-17

Create a LocalDate object representing the current date from a specified clock:


Clock clock = Clock.systemDefaultZone();

LocalDate localDate = LocalDate.now(clock);
System.out.println("localDate.now(clock): " + localDate);

TODO Link?

Create a LocalDate object representing the current date from a specified ZoneId:


// Default system time-zone.
ZoneId zoneIdDefault = ZoneId.systemDefault();
        
// Ho Chi Minh City, Vietnam. UTC+7
ZoneId zoneId = ZoneId.of("Asia/Ho_Chi_Minh");

LocalDate localDate = LocalDate.now(zoneId);
System.out.println("localDate: " + localDate); // 2021-06-17

Java ZoneId

Create a LocalDate object from the specified year, month, dayOfMonth:


// Ex: LocalDate based on year, month, dayOfMonth.
LocalDate localDate1 = LocalDate.of(2000, 5, 20); // 2000-05-20
System.out.println("localDate1: " + localDate1);

LocalDate localDate2 = LocalDate.of(2000, Month.MAY, 20); // 2000-05-20
System.out.println("localDate2: " + localDate2);

Create a LocalDate object from the specified year, dayOfYear:


// Ex: LocalDate based on year and dayOfYear
LocalDate localDate1 = LocalDate.ofYearDay(1995, 1); // 1995-01-01 + 0 days.
System.out.println("localDate1: " + localDate1); // 1995-01-01

LocalDate localDate2 = LocalDate.ofYearDay(1995, 51); // 1995-01-01 + 50 days.
System.out.println("localDate2: " + localDate2); // 1995-02-20

Create a LocalDate object from the specified epochDay:


// Ex: LocalDate based on epochDay.
LocalDate localDate1 = LocalDate.ofEpochDay(0); // 1971-01-01 + 0 days.
System.out.println("localDate1: " + localDate1); // 1970-01-01

LocalDate localDate2 = LocalDate.ofEpochDay(1000); // 1971-01-01 + 1000 days.
System.out.println("localDate2: " + localDate2); // 1972-09-27

Create a LocalDate object from Instant and ZoneId objects:


Instant instant = Instant.now();
ZoneId zoneId = ZoneId.systemDefault();

// LocalDate based on Instant and ZoneId.
LocalDate localDate = LocalDate.ofInstant(instant, zoneId);
System.out.println("localDate: " + localDate);

ZoneId

Create a LocalDate object from parsing a date formatted text:


// Ex: LocalDate based on CharSequence.
LocalDate localDate1 = LocalDate.parse("2011-11-20");
System.out.println("localDate1: " + localDate1); // 2011-11-20

// Ex: LocalDate based on CharSequence and DateTimeFormatter
DateTimeFormatter fmt2 = DateTimeFormatter.ofPattern("dd/MM/yyyy");

LocalDate localDate2 = LocalDate.parse("20/11/2020", fmt2);
System.out.println("localDate2: " + localDate2); // 2011-11-20

ZonedDateTime

3- format(DateTimeFormatter)

Format this LocalDate object with a specified DateTimeFormatter object.


// Inherited from ChronoLocalDate interface
public String format(DateTimeFormatter formatter)

Example:

LocalDate_format_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

DateTimeFormatter fmt1 = DateTimeFormatter.BASIC_ISO_DATE; // yyyyMMdd  
System.out.println("BASIC_ISO_DATE: " + localDate.format(fmt1)); // 20200515

DateTimeFormatter fmt2 = DateTimeFormatter.ofPattern("dd/MM/yyyy");  
System.out.println("dd/MM/yyyy: " + localDate.format(fmt2)); // 15/05/2020

TODO Link?

4- isBefore(..), isAfter(..)

The isBefore(ChronoLocalDate) method is used to check if this LocalDate object is before another specified object on the timeline.


// Inherited from ChronoLocalDate interface
public boolean isBefore(ChronoLocalDate other)

The isAfter(ChronoLocalDate) method is used to check if this LocalDate object is after another specified object on the timeline.


// Inherited from ChronoLocalDate interface
public boolean isAfter(ChronoLocalDate other)

localDate1 is before localDate2.


LocalDate localDate1 = LocalDate.parse("1990-05-15"); // 1990-May-15
LocalDate localDate2 = LocalDate.parse("2020-12-15"); // 2020-Dec-15


System.out.println("localDate1: " + localDate1); // 1990-05-15
System.out.println("localDate2: " + localDate2); // 2020-12-15
System.out.println();

System.out.println("localDate1.isBefore(localDate2): " + localDate1.isBefore(localDate2)); // true
System.out.println("localDate1.isAfter(localDate2): " + localDate1.isAfter(localDate2)); // false

Output:


localDate1: 1990-05-15
localDate2: 2020-12-15

localDate1.isBefore(localDate2): true
localDate1.isAfter(localDate2): false

TODO Link?

5- lengthOfMonth(), lengthOfYear()

The lengthOfMonth() method returns the number of days in the month represented by this LocalDate object.

The lengthOfYear() method returns the number of days in the year represented by this LocalDate object.


public int lengthOfMonth()  

public int lengthOfYear()

Example:

LocalDate_lengthX_ex1.java


package org.codewr.localdate.ex;

import java.time.LocalDate;

public class LocalDate_lengthX_ex1 {

    public static void main(String[] args) {
        LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
        System.out.println("localDate: " + localDate); // 2020-05-15
        System.out.println();
        
        System.out.println("localDate.lengthOfMonth(): " + localDate.lengthOfMonth());  // 31 days
        System.out.println("localDate.lengthOfYear(): " + localDate.lengthOfYear()); // 366 days
    }
}

6- getX() *

The getYear() method returns the year represented by this LocalDate. It is equivalent to calling the get(ChronoField.YEAR) method. If you want to get the year of the era, call the get(ChronoField. YEAR_OF_ERA).


public int getYear()  
public int getMonthValue()   
public Month getMonth()
public int getDayOfMonth()
public int getDayOfYear()
public DayOfWeek getDayOfWeek()  
public IsoEra getEra()  
public IsoChronology getChronology()

The other methods getMonthValue(), getMonth(), getDayOfMonth(), getDayOfYear(), getDayOfWeek(), ... are also understood as their names.

Method	Same As
getYear()	localDate.get(ChronoField.YEAR)
getMonthValue()	localDate.get(ChronoField.MONTH_OF_YEAR)
getMonth()	Month.of(localDate.get(ChronoField.MONTH_OF_YEAR))
getDayOfMonth()	localDate.get(ChronoField.DAY_OF_MONTH)
getDayOfYear()	localDate.get(ChronoField.DAY_OF_YEAR)
getDayOfWeek()	DayOfWeek.of(localDate.get(ChronoField.DAY_OF_WEEK))
getEra()	localDate.get(ChronoField.ERA)
getChronology()	localDate.get(ChronoField.CHRONOLOGY)

Example:

LocalDate_getX_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

System.out.println("localDate.getEra(): " + localDate.getEra());  // IsoEra.CE  (enum)
System.out.println("localDate.getDayOfYear(): " + localDate.getDayOfYear()); // 136
System.out.println("localDate.getDayOfMonth(): " + localDate.getDayOfMonth()); // 15
System.out.println("localDate.getYear(): " + localDate.getYear());  // 2020
System.out.println("localDate.getMonth(): " + localDate.getMonth());  // Month.MAY (enum)
System.out.println("localDate.getMonthValue(): " + localDate.getMonthValue()); // 5
System.out.println("localDate.getDayOfWeek(): " + localDate.getDayOfWeek()); // DayOfWeek.FRIDAY (enum)

Output:


localDate: 2020-05-15

localDate.getEra(): CE
localDate.getDayOfYear(): 136
localDate.getDayOfMonth(): 15
localDate.getYear(): 2020
localDate.getMonth(): MAY
localDate.getMonthValue(): 5
localDate.getDayOfWeek(): FRIDAY

7- get(TemporalField)

Return the value of the specified field of this LocalDate object as a 32-bit integer.


// Inherited from TemporalAccessor interface
public int get(TemporalField field)

Note: Some fields may not be supported by LocalDate and an UnsupportedTemporalTypeException will be thrown. To be sure, use the isSupported(TemporalField) method to check if a certain field is supported by LocalDate.

Example:

LocalDate_get_field_ex1.java


LocalDate date = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + date); // 2020-05-15
System.out.println();

// int get(TemporalField field)
System.out.println("DAY_OF_MONTH: " + date.get(ChronoField.DAY_OF_MONTH)); // 15
System.out.println("DAY_OF_WEEK: " + date.get(ChronoField.DAY_OF_WEEK)); // 5
System.out.println("DAY_OF_YEAR: " + date.get(ChronoField.DAY_OF_YEAR)); // 136
System.out.println("ERA: " + date.get(ChronoField.ERA)); // 1
System.out.println("YEAR: " + date.get(ChronoField.YEAR)); // 2020
System.out.println("YEAR_OF_ERA: " + date.get(ChronoField.YEAR_OF_ERA)); // 2020
System.out.println("ALIGNED_DAY_OF_WEEK_IN_MONTH: " + date.get(ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH)); // 1
System.out.println("ALIGNED_DAY_OF_WEEK_IN_YEAR: " + date.get(ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR)); // 3
System.out.println("ALIGNED_WEEK_OF_MONTH: " + date.get(ChronoField.ALIGNED_WEEK_OF_MONTH)); // 3
System.out.println("ALIGNED_WEEK_OF_YEAR: " + date.get(ChronoField.ALIGNED_WEEK_OF_YEAR)); // 20

// Use getLong() instead
// System.out.println("PROLEPTIC_MONTH: " + date.get(ChronoField.PROLEPTIC_MONTH)); // 24244
// System.out.println("EPOCH_DAY: " + date.get(ChronoField.EPOCH_DAY)); // 18397

8- getLong(TemporalField)

Return the value of the specified field of this LocalDate object as a 64-bit integer.


// Inherited from TemporalAccessor interface
public long getLong(TemporalField field)

Example:

LocalDate_getLong_field_ex1.java


LocalDate date = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + date); // 2020-05-15
System.out.println();

// long getLong(TemporalField field)
System.out.println("DAY_OF_MONTH: " + date.getLong(ChronoField.DAY_OF_MONTH)); // 15
System.out.println("DAY_OF_WEEK: " + date.getLong(ChronoField.DAY_OF_WEEK)); // 5
System.out.println("DAY_OF_YEAR: " + date.getLong(ChronoField.DAY_OF_YEAR)); // 136
System.out.println("ERA: " + date.getLong(ChronoField.ERA)); // 1
System.out.println("YEAR: " + date.getLong(ChronoField.YEAR)); // 2020
System.out.println("YEAR_OF_ERA: " + date.getLong(ChronoField.YEAR_OF_ERA)); // 2020
System.out.println("ALIGNED_DAY_OF_WEEK_IN_MONTH: " + date.getLong(ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH)); // 1
System.out.println("ALIGNED_DAY_OF_WEEK_IN_YEAR: " + date.getLong(ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR)); // 3
System.out.println("ALIGNED_WEEK_OF_MONTH: " + date.getLong(ChronoField.ALIGNED_WEEK_OF_MONTH)); // 3
System.out.println("ALIGNED_WEEK_OF_YEAR: " + date.getLong(ChronoField.ALIGNED_WEEK_OF_YEAR)); // 20

System.out.println("PROLEPTIC_MONTH: " + date.getLong(ChronoField.PROLEPTIC_MONTH)); // 24244
System.out.println("EPOCH_DAY: " + date.getLong(ChronoField.EPOCH_DAY)); // 18397

9- plusX(..) *

The plusYear(yearsToAdd) method returns a copy of this LocalDate object with the specified amount of years added.

The methods plusMonths(monthsToAdd), plusWeeks(weeksToAdd), plusDays(daysToAdd) are also understood as the names imply.


public LocalDate plusYears(long yearsToAdd)  
public LocalDate plusMonths(long monthsToAdd)  
public LocalDate plusWeeks(long weeksToAdd)
public LocalDate plusDays(long daysToAdd)

Example:

LocalDate_plusX_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// plusDays(long daysToAdd)
LocalDate localDate1 = localDate.plusDays(10);
System.out.println("localDate1: " + localDate1); // 2020-05-25

LocalDate localDate2 = localDate.plusDays(-15);
System.out.println("localDate2: " + localDate2); // 2020-04-30

// plusMonths(long monthsToAdd)
LocalDate localDate3 = localDate.plusMonths(3);
System.out.println("localDate3: " + localDate3); // 2020-08-15

// plusYears(long yearsToAdd)
LocalDate localDate4 = localDate.plusYears(1);
System.out.println("localDate4: " + localDate4); // 2021-05-15

// plusWeeks(long weeksToAdd)
LocalDate localDate5 = localDate.plusWeeks(2);
System.out.println("localDate5: " + localDate5); // 2020-05-29

Output:


localDate: 2020-05-15

localDate1: 2020-05-25
localDate2: 2020-04-30
localDate3: 2020-08-15
localDate4: 2021-05-15
localDate5: 2020-05-29

10- plus(TemporalAmount)

Return a copy of this LocalDate object with an added amount of time.


// Inherited from Temporal interface
public LocalDate plus(TemporalAmount amountToAdd)

Example:

LocalDate_plus_amount_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// plus(TemporalAmount amountToAdd)
TemporalAmount amount1 = Period.ofDays(5);
LocalDate localDate1 = localDate.plus(amount1);
System.out.println("localDate1: " + localDate1); // 2020-05-20

// plus(TemporalAmount amountToAdd)
LocalDate from = LocalDate.of(2020, 5, 10);
LocalDate to = LocalDate.of(2020, 5, 12);

TemporalAmount amount2 = Period.between(from, to); // 2 days
LocalDate localDate2 = localDate.plus(amount2);
System.out.println("localDate2: " + localDate2

Output:


localDate: 2020-05-15

localDate1: 2020-05-20
localDate2: 2020-05-17

Period

11- plus(long, TemporalUnit)

Return a copy of this LocalDate object with a specified value added in the given unit.


// Inherited from Temporal interface
public LocalDate plus(long amountToAdd, TemporalUnit unit)

Example:

LocalDate_plus_unit_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// plus(long amountToAdd, TemporalUnit unit)
LocalDate localDate1 = localDate.plus(5, ChronoUnit.DAYS);
System.out.println("localDate1: " + localDate1); // 2020-05-20

// plus(long amountToAdd, TemporalUnit unit)
LocalDate localDate2 = localDate.plus(10, ChronoUnit.MONTHS);
System.out.println("localDate2: " + localDate2); // 2021-03-15

Output:


localDate: 2020-05-15

localDate1: 2020-05-20
localDate2: 2021-03-15

ChronoUnit

12- minusX(..) *

The minusYears(yearsToSubtract) method returns a copy of this LocalDate object with the specified amount of years subtracted.

The methods minusMonths(monthsToSubtract), minusWeeks(weeksToSubtract), minusDays(daysToSubtract) is also understood as their names.


public LocalDate minusYears(long yearsToSubtract)  
public LocalDate minusMonths(long monthsToSubtract)  
public LocalDate minusWeeks(long weeksToSubtract)  
public LocalDate minusDays(long daysToSubtract)

Example:


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// minusDays(long daysToSubtract)
LocalDate localDate1 = localDate.minusDays(10);
System.out.println("localDate1: " + localDate1); // 2020-05-05

LocalDate localDate2 = localDate.minusDays(-10);
System.out.println("localDate2: " + localDate2); // 2020-05-25

// minusMonths(long monthsToSubtract)
LocalDate localDate3 = localDate.minusMonths(3);
System.out.println("localDate3: " + localDate3); // 2020-02-15

// minusYears(long yearsToSubtract)
LocalDate localDate4 = localDate.minusYears(1);
System.out.println("localDate4: " + localDate4); // 2019-05-15

// minusWeeks(long weeksToSubtract)
LocalDate localDate5 = localDate.minusWeeks(2);
System.out.println("localDate5: " + localDate5); // 2020-05-01

// minus(TemporalAmount)
TemporalAmount amount6 = Period.ofDays(5);
LocalDate localDate6 = localDate.minus(amount6);
System.out.println("localDate6: " + localDate6); // 2020-05-10

// minus(TemporalAmount)
LocalDate from = LocalDate.of(2020, 5, 10);
LocalDate to = LocalDate.of(2020, 5, 12);

TemporalAmount amount7 = Period.between(from, to); // 2 days
LocalDate localDate7 = localDate.minus(amount7);
System.out.println("localDate7: " + localDate7); // 2020-05-13

// minus(long amountToSubtract, TemporalUnit unit)
TemporalUnit unit = ChronoUnit.DAYS;
LocalDate localDate8 = localDate.minus(3, unit);

System.out.println("localDate8: " + localDate8); // 2020-05-12

Output:


localDate: 2020-05-15

localDate1: 2020-05-05
localDate2: 2020-05-25
localDate3: 2020-02-15
localDate4: 2019-05-15
localDate5: 2020-05-01
localDate6: 2020-05-10
localDate7: 2020-05-13
localDate8: 2020-05-12

13- minus(TemporalAmount)

Return a copy of this LocalDate object with the amount of time subtracted.


// Inherited from Temporal interface.
public LocalDate minus(TemporalAmount amountToSubtract)

Example:

LocalDate_minus_amount_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// minus(TemporalAmount amountToSubtract)
TemporalAmount amount1 = Period.ofDays(5);
LocalDate localDate1 = localDate.minus(amount1);
System.out.println("localDate1: " + localDate1); // 2020-05-10

// minus(TemporalAmount amountToSubtract)
LocalDate from = LocalDate.of(2020, 5, 10);
LocalDate to = LocalDate.of(2020, 5, 12);

TemporalAmount amount2 = Period.between(from, to); // 2 days
LocalDate localDate2 = localDate.minus(amount2);
System.out.println("localDate2: " + localDate2); // 2020-05-13

Period

14- minus(long, TemporalUnit)

Return a copy of this LocalDate object with a specified value subtracted in given unit.


// Inherited from Temporal interface.
public LocalDate minus(long amountToSubtract, TemporalUnit unit)

Example:

LocalDate_minus_unit_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15
System.out.println("localDate: " + localDate); // 2020-05-15
System.out.println();

// minus(long amountToSubtract, TemporalUnit unit)
LocalDate localDate1 = localDate.minus(5, ChronoUnit.DAYS);
System.out.println("localDate1: " + localDate1); // 2020-05-10

// minus(long amountToSubtract, TemporalUnit unit)
LocalDate localDate2 = localDate.minus(10, ChronoUnit.MONTHS);
System.out.println("localDate2: " + localDate2); // 2019-07-15

ChronoUnit

15- withX(..) *


public LocalDate withYear(int year)  

public LocalDate withMonth(int month)  

public LocalDate withDayOfMonth(int dayOfMonth)

public LocalDate withDayOfYear(int dayOfYear)

The withYear(year) method returns a copy of this LocalDate object with the year changed. If the day-of-month is not valid for the year, it will be changed to the last valid day of month.

LocalDate_withYear_ex1.java


LocalDate localDate1 = LocalDate.parse("2020-02-29").withYear(2024);  
System.out.println("localDate1: " + localDate1); // 2024-02-29

LocalDate localDate2 = LocalDate.parse("2020-02-29").withYear(2019); // Important Note!
System.out.println("localDate2: " + localDate2); // 2019-02-28

LocalDate localDate3 = LocalDate.parse("2020-02-28").withYear(2019);  
System.out.println("localDate3: " + localDate3); // 2019-02-28

LocalDate localDate4 = LocalDate.parse("2020-02-21").withYear(2019);  
System.out.println("localDate4: " + localDate4); // 2019-02-21

The withMonth(month) method returns a copy of this LocalDate object with the month changed. If the day-of-month is not valid for the year, it will be changed to the last valid day-of-month.

LocalDate_withMonth_ex1.java


LocalDate localDate1 = LocalDate.parse("2020-03-31").withMonth(2); // Important Note!
System.out.println("localDate1: " + localDate1); // 2020-02-29

LocalDate localDate2 = LocalDate.parse("2020-03-31").withMonth(2); // Important Note!
System.out.println("localDate2: " + localDate2); // 2020-02-29

LocalDate localDate3 = LocalDate.parse("2020-03-29").withMonth(2);  
System.out.println("localDate3: " + localDate3); // 2019-02-28

LocalDate localDate4 = LocalDate.parse("2020-03-21").withMonth(2);  
System.out.println("localDate4: " + localDate4); // 2020-02-21

The withDayOfMonth(dayOfMonth) method returns a copy of this LocalDate object with the day-of-month changed. If the day-of-month is invalid, a DateTimeException is thrown.

LocalDate_withDayOfMonth_ex1.java


LocalDate localDate1 = LocalDate.parse("2020-02-01").withDayOfMonth(15);  
System.out.println("localDate1: " + localDate1); // 2020-02-15

LocalDate localDate2 = LocalDate.parse("2020-02-01").withDayOfMonth(29);  
System.out.println("localDate2: " + localDate2); // 2020-02-29

// Invalid date.
// Throws java.time.DateTimeException: Invalid date 'FEBRUARY 30'
LocalDate localDate3 = LocalDate.parse("2020-02-01").withDayOfMonth(30);  
System.out.println("localDate3: " + localDate3);

Output:


localDate1: 2020-02-15
localDate2: 2020-02-29
Exception in thread "main" java.time.DateTimeException: Invalid date 'FEBRUARY 30'
    at java.base/java.time.LocalDate.create(LocalDate.java:459)
    at java.base/java.time.LocalDate.of(LocalDate.java:271)
    at java.base/java.time.LocalDate.withDayOfMonth(LocalDate.java:1124)
    at org.codewr.localdate.ex.LocalDate_withDayOfMonth_ex1.main(LocalDate_withDayOfMonth_ex1.java:17)

The withDayOfYear(dayOfYear) method returns a copy of this LocalDate object with the day-of-year changed. If dayOfYear is not valid then a DateTimeException is thrown, valid values from 1 to 365 (Or 366).

LocalDate_withDayOfYear_ex1.java


LocalDate localDate1 = LocalDate.parse("2020-02-01").withDayOfYear(15);  
System.out.println("localDate1: " + localDate1); // 2020-01-15

LocalDate localDate2 = LocalDate.parse("2020-02-01").withDayOfYear(29);  
System.out.println("localDate2: " + localDate2); // 2020-01-29

LocalDate localDate3 = LocalDate.parse("2020-02-01").withDayOfYear(35);  
System.out.println("localDate3: " + localDate3); // 2020-02-04

16- with(TemporalAdjuster)

Return a copy of this LocalDate object, with the date data adjusted by the TemporalAdjuster object.


// Inherited from Temporal interface
public LocalDate with(TemporalAdjuster adjuster)

Example:

LocalDate_with_adjuster_ex1.java


LocalDate now = LocalDate.now();
System.out.println("Now is: " + now);
System.out.println();

LocalDate firstDayOfMonth = now.with(TemporalAdjusters.firstDayOfMonth());
System.out.println("firstDayOfMonth: " + firstDayOfMonth);

LocalDate nextMonday = now.with(TemporalAdjusters.next(DayOfWeek.MONDAY));
System.out.println("nextMonday: " + nextMonday);

LocalDate firstDayOfNextYear = now.with(TemporalAdjusters.firstDayOfNextYear());
System.out.println("firstDayOfNextYear: " + firstDayOfNextYear);

Output:


Now is: 2021-06-01

firstDayOfMonth: 2021-06-01
nextMonday: 2021-06-07
firstDayOfNextYear: 2022-01-01

Example: Write a custom TemporalAdjuster to find the next Christmas date.

LocalDate_with_adjuster_ex2.java


package org.codewr.localdate.ex;

import java.time.LocalDate;
import java.time.Period;
import java.time.temporal.ChronoField;
import java.time.temporal.Temporal;
import java.time.temporal.TemporalAdjuster;

public class LocalDate_with_adjuster_ex2 {

    public static void main(String[] args) {
        LocalDate localDate = LocalDate.parse("2020-12-28");
        System.out.println("Date : " + localDate);

        // with(TemporalAdjuster):
        LocalDate localDate2 = localDate.with(new NextChristmas());
        System.out.println("Next Christmas : " + localDate2);
    }
}

class NextChristmas implements TemporalAdjuster {

    @Override
    public Temporal adjustInto(Temporal temporal) {
        int month = temporal.get(ChronoField.MONTH_OF_YEAR);
        int day = temporal.get(ChronoField.DAY_OF_MONTH);
        if(month == 12 && day > 25)  {
            temporal = temporal.plus(Period.ofYears(1));
        }
        return temporal.with(ChronoField.MONTH_OF_YEAR, 12).with(ChronoField.DAY_OF_MONTH, 25);
    }
}

Output:


Date : 2020-12-28
Next Christmas : 2021-12-25

17- with(TemporalField, long)

Return a copy of this LocalDate object with the specified field changed to the new value.


// Inherited from Temporal interface
public LocalDate with(TemporalField field, long newValue)

In some cases, changing the specified field can cause the resulting date to become invalid, such as changing the month from 31st January to February would make the day-of-month invalid. In cases like this, this problem has been handled by this method. Typically it will choose the previous valid date, which would be the last valid day of February in this example.

Example:

LocalDate_with_field_ex1.java


LocalDate myDate = LocalDate.parse("2021-05-29");

System.out.println("myDate is: " + myDate);
System.out.println("myDate day of week: " + myDate.get(ChronoField.DAY_OF_WEEK));  // 6
System.out.println("myDate day of month: " + myDate.get(ChronoField.DAY_OF_MONTH)); // 29
System.out.println();

LocalDate localDate1 =    myDate.with(ChronoField.DAY_OF_WEEK, 3);   
System.out.println("localDate1: " + localDate1); // 2021-05-26

LocalDate localDate2 =    myDate.with(ChronoField.DAY_OF_MONTH, 10);  
System.out.println("localDate2: " + localDate2);  // 2021-05-10

// February 2021 has only 28 days.
LocalDate localDate3 =    myDate.with(ChronoField.MONTH_OF_YEAR, 2);  
System.out.println("localDate3: " + localDate3);  // 2021-02-28  (***)

Output:


myDate is: 2021-05-29
myDate day of week: 6
myDate day of month: 29

localDate1: 2021-05-26
localDate2: 2021-05-10
localDate3: 2021-02-28

18- range(TemporalField)

Return the range of valid values for the specified field.


//  Inherited from TemporalAccessor interface
public ValueRange range(TemporalField field)

Example:

LocalDate_range_ex1.java


LocalDate localDate   = LocalDate.parse("2021-06-18");  
System.out.println("LocalDate: "  + localDate);
 
// range(TemporalField field)
ValueRange range = localDate.range(ChronoField.DAY_OF_MONTH);
 
// Print range of DAY_OF_MONTH
System.out.println("Range of DAY_OF_MONTH: "  + range); // 1 - 30

System.out.println("First day of this month: " + range.getMinimum()); // 1
System.out.println("Last day of this month: " + range.getMaximum()); // 30

ValueRange range2 = localDate.range(ChronoField.DAY_OF_YEAR);
System.out.println("Range of DAY_OF_YEAR: "  + range2); // 1 - 365

19- query(TemporalQuery<R>)

Query this LocalDate object with the given TemporalQuery parameter to extract information.


// Inherited from TemporalAccessor interface
public <R> R query(TemporalQuery<R> query)

Example:

LocalDate_query_ex1.java


package org.codewr.localdate.ex;

import java.time.LocalDate;
import java.time.temporal.TemporalQueries;

public class LocalDate_query_ex1 {

    public static void main(String[] args) {
        LocalDate localDate = LocalDate.parse("2021-05-15");

        // Apply query method of LocalDate class
        String value = localDate.query(TemporalQueries.precision()).toString();

        // Print the result
        System.out.println("Precision value for LocalDate is " + value);

        // Apply query method of LocalDate class
        System.out.println("Zone value for LocalDate is " + localDate.query(TemporalQueries.offset()));
    }
}

Output:


Precision value for LocalDate is Days
Zone value for LocalDate is null

20- isLeapYear()

Check if the year represented in this LocalDate object is a leap year.


// Inherited from ChronoLocalDate interface
public boolean isLeapYear()

Basically, in the ISO calendar system, a year is considered a leap year if it is divisible by 4. However a year divisible by 100 is not a leap year except when it is divisible by 400.

So:

1904 is a leap year because it was divisible by 4 and not divisible by 100.
1900 is not a leap year because it is divisible by 100 but not by 400.
2000 is a leap year because it is divisible by 400.

21- isSupported(TemporalField)

Check if a given TemporalField is supported.


// Inherited from TemporalAccessor interface
public boolean isSupported(TemporalField field)

Basically, LocalDate supports the following TemporalField(s):

ChronoField.DAY_OF_WEEK
ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH
ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR
ChronoField.DAY_OF_MONTH
ChronoField.DAY_OF_YEAR
ChronoField.EPOCH_DAY
ChronoField.ALIGNED_WEEK_OF_MONTH
ChronoField.ALIGNED_WEEK_OF_YEAR
ChronoField.MONTH_OF_YEAR
ChronoField.PROLEPTIC_MONTH
ChronoField.YEAR_OF_ERA
ChronoField.YEAR
ChronoField.ERA

Example:

LocalDate_isSupported_ex1.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15

// boolean isSupported(TemporalField field)
// LocalDate does not support ChronoField.MINUTE_OF_DAY, HOUR_OF_DAY,.. (** Used for LocalDateTime, LocalTime)
System.out.println("MINUTE_OF_DAY is supported? " + localDate.isSupported(ChronoField.MINUTE_OF_DAY)); // false
System.out.println("HOUR_OF_DAY is supported? " + localDate.isSupported(ChronoField.HOUR_OF_DAY)); // false

// LocalDate support ChronoField.MONTH_OF_YEAR, DAY_OF_WEEK,..
System.out.println("MONTH_OF_YEAR is supported? " + localDate.isSupported(ChronoField.MONTH_OF_YEAR)); // true
System.out.println("DAY_OF_WEEK is supported? " + localDate.isSupported(ChronoField.DAY_OF_WEEK)); // true

22- isSupported(TemporalUnit)

Check if a specified TemporalUnit is supported.


// Inherited from Temporal interface
public boolean isSupported(TemporalUnit unit)

Basically, LocalDate supports the following TemporalUnit(s):

ChronoUnit.DAYS
ChronoUnit.WEEKS
ChronoUnit.MONTHS
ChronoUnit.YEARS
ChronoUnit.DECADES
ChronoUnit.CENTURIES
ChronoUnit.MILLENNIA
ChronoUnit.ERAS

Example:

LocalDate_isSupported_ex2.java


LocalDate localDate = LocalDate.parse("2020-05-15"); // 2020-May-15

// boolean isSupported(TemporalUnit unit)
// LocalDate does not support ChronoUnit.HOURS, MINUTES,.. (** Used for LocalDateTime, LocalTime)
System.out.println("HOURS is supported? " + localDate.isSupported(ChronoUnit.HOURS)); // false
System.out.println("MINUTES is supported? " + localDate.isSupported(ChronoUnit.MINUTES)); // false

// LocalDate support ChronoUnit.CENTURIES, WEEKS,..
System.out.println("CENTURIES is supported? " + localDate.isSupported(ChronoUnit.CENTURIES)); // true
System.out.println("WEEKS is supported? " + localDate.isSupported(ChronoUnit.WEEKS)); // true

ChronoUnit