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Java LocalTime

Java LocalTime tutorial shows how to work with LocalTime in Java. We compute the current local time, parse local time, format local time, compare local time, and do time arithmetics.

Java LocalTime

LocalTime is a time without a time-zone in the ISO-8601 calendar system. LocalTime is an immutable date-time object.

LocalTime does not store or represent a date or time-zone. It is a description of the local time as seen on a wall clock. Wall time, also called real-world time or wall-clock time, refers to elapsed time as determined by a chronometer such as a wristwatch or wall clock.

The equals() method should be used for comparisons.

Java LocalTime current time

The current time is retrived with LocalTime.now().

JavaLocalTimeNow.java
package com.zetcode;

import java.time.LocalTime;

public class JavaLocalTimeNow {

    public static void main(String[] args) {

        LocalTime now = LocalTime.now();
        System.out.println(now);
    }
}

The example prints the local current time.

18:12:05.172

This is the output.

Java LocalTime create

The are several ways to create LocalTime in Java.

JavaLocalTimeCreate.java
package com.zetcode;

import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

public class JavaLocalTimeCreate {

    public static void main(String[] args) {

        // Current Time
        LocalTime time1 = LocalTime.now();
        System.out.println(time1);

        // Specific Time
        LocalTime time2 = LocalTime.of(7, 20, 45, 342123342);
        System.out.println(time2);

        // Specific Time
        LocalTime time3 = LocalTime.parse("12:32:22", 
            DateTimeFormatter.ISO_TIME);
        System.out.println(time3);
        
        // Retrieving from LocalDateTime
        LocalTime time4 = LocalDateTime.now().toLocalTime();
        System.out.println(time4);
    }
}

The example presents four methods

LocalTime time1 = LocalTime.now();

The LocalTime.now() creates a current local time.

LocalTime time2 = LocalTime.of(7, 20, 45, 342123342);

With LocalTime.of(), we can create a specific local time from an hour, minute, second and nanosecond.

LocalTime time3 = LocalTime.parse("12:32:22", 
            DateTimeFormatter.ISO_TIME);

With LocalTime.parse(), we parse LocalTime from a string.

LocalTime time4 = LocalDateTime.now().toLocalTime();

It is also possible to get LocalTime from a LocalDateTime object.

18:18:12.135
07:20:45.342123342
12:32:22
18:18:12.186

This is the output.

Java LocalTime hour, minute, second

The following example splits a local time into hour, minute, and second parts.

JavaLocalTimeParts.java
package com.zetcode;

import java.time.LocalTime;

public class JavaLocalTimeParts {

    public static void main(String[] args) {

        LocalTime time = LocalTime.now();

        System.out.printf("Hour: %s%n", time.getHour());
        System.out.printf("Minute: %s%n", time.getMinute());
        System.out.printf("Second: %s%n", time.getSecond());
    }
}

The getHour() gets the hour part, the getMinute() gets the minute part, and the getSecond() the second part of the LocalTime.

Hour: 18
Minute: 25
Second: 55

This is the output.

Java LocalTime zones

We can compute a local time for a specific time zone. LocalTime, however, does not store time zone information.

JavaLocalTimeZone.java
package com.zetcode;

import java.time.LocalTime;
import java.time.ZoneId;
import java.time.temporal.ChronoUnit;

public class JavaLocalTimeZone {

    public static void main(String[] args) {

        ZoneId zone1 = ZoneId.of("Europe/Bratislava");
        ZoneId zone2 = ZoneId.of("Europe/Moscow");

        LocalTime now1 = LocalTime.now(zone1);
        LocalTime now2 = LocalTime.now(zone2);

        System.out.printf("Bratislava time: %s%n", now1);
        System.out.printf("Moscow time: %s%n", now2);

        long hoursBetween = ChronoUnit.HOURS.between(now1, now2);
        long minutesBetween = ChronoUnit.MINUTES.between(now1, now2);
        
        System.out.println(hoursBetween);
        System.out.println(minutesBetween);
    }
}

The example finds out current local time for Moscow and Bratislava. We also compute the time difference between the two cities.

ZoneId zone1 = ZoneId.of("Europe/Bratislava");
ZoneId zone2 = ZoneId.of("Europe/Moscow");

We specify the time zones with ZoneId.of() method.

LocalTime now1 = LocalTime.now(zone1);
LocalTime now2 = LocalTime.now(zone2);

To create local times, we pass the zones to the LocalTime.now().

long hoursBetween = ChronoUnit.HOURS.between(now1, now2);
long minutesBetween = ChronoUnit.MINUTES.between(now1, now2);

We compute the difference between the two cities in hours and minutes.

Bratislava time: 11:00:42.704
Moscow time: 13:00:42.732
2
120

This is the output.

Java LocalTime format

The time is formatted differently in various countries. DateTimeFormatter helps us format the time.

JavaLocalTimeFormat.java
package com.zetcode;

import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

public class JavaLocalTimeFormat {

    public static void main(String[] args) {
        
        LocalTime now = LocalTime.now();
        
        DateTimeFormatter dtf = DateTimeFormatter.ISO_TIME;
        System.out.println(now.format(dtf));     
        
        DateTimeFormatter dtf2 = DateTimeFormatter.ofPattern("hh:mm:ss");
        System.out.println(now.format(dtf2));   
        
        DateTimeFormatter dtf3 = DateTimeFormatter.ofPattern("hh:mm:ss a");
        System.out.println(now.format(dtf3));           
    }
}

The example uses DateTimeFormatter to format time.

DateTimeFormatter dtf = DateTimeFormatter.ISO_TIME;
System.out.println(now.format(dtf)); 

We format the time to the ISO format time standart.

DateTimeFormatter dtf2 = DateTimeFormatter.ofPattern("hh:mm:ss");

We can choose a specific time format with DateTimeFormatter.ofPattern(). The documentation to DateTimeFormatter contains the description of various formatting characters that we can use.

11:08:56.483
11:08:56
11:08:56 AM

This is the output.

Java LocalTime arithmetic

Java LocalTime has methods for doing time arithmetics.

JavaLocalTimeArithmetic.java
package com.zetcode;

import java.time.LocalTime;

public class JavaLocalTimeArithmetic {

    public static void main(String[] args) {
        
        LocalTime now = LocalTime.now();
        System.out.println("Current Time: " + now);

        // LocalTime addition
        System.out.println("Adding 3 hours: " + now.plusHours(3));
        System.out.println("Adding 30 minutes: " + now.plusMinutes(30));
        System.out.println("Adding 45 seconds: " + now.plusSeconds(45));
        System.out.println("Adding 40000 nanoseconds: " + now.plusNanos(40000));

        // LocalTime subtraction
        System.out.println("Subtracting 3 hours: " + now.minusHours(3));
        System.out.println("Subtracting 30 minutes: " + now.minusMinutes(30));
        System.out.println("Subtracting 45 seconds: " + now.minusSeconds(45));
        System.out.println("Subtracting 40000 nanoseconds: " + now.minusNanos(40000));
    }
}

The example presents method for adding and subtracting time units.

System.out.println("Adding 3 hours: " + localTime.plusHours(3));

The plusHours() adds three hours to the current local time.

System.out.println("Subtracting 3 hours: " + now.minusHours(3));

Likewise, the minusHours() subtracts three hours from the current local time.

Current Time: 11:12:51.155
Adding 3 hours: 14:12:51.155
Adding 30 minutes: 11:42:51.155
Adding 45 seconds: 11:13:36.155
Adding 40000 nanoseconds: 11:12:51.155040
Subtracting 3 hours: 08:12:51.155
Subtracting 30 minutes: 10:42:51.155
Subtracting 45 seconds: 11:12:06.155
Subtracting 40000 nanoseconds: 11:12:51.154960

This is the output.

Java LocalTime until

With the until() method, we can compute the time until another time in terms of the specified unit.

JavaLocalTimeUntil.java
package com.zetcode;

import java.time.LocalTime;
import java.time.temporal.ChronoUnit;

public class JavaLocalTimeUntil {

    public static void main(String[] args) {

        LocalTime now = LocalTime.now();
        LocalTime time = LocalTime.parse("22:15:30");
        
        System.out.printf("%s hours%n", now.until(time, ChronoUnit.HOURS));
        System.out.printf("%s minutes%n", now.until(time, ChronoUnit.MINUTES));
        System.out.printf("%s seconds%n", now.until(time, ChronoUnit.SECONDS));
    }
}

The example calculates the time that has to elapse until another time in hours, minutes and seconds.

System.out.printf("%s hours%n", now.until(time, ChronoUnit.HOURS));

With ChronoUnit.HOURS, we specify that we calculate the the time difference in hours.

10 hours
657 minutes
39476 seconds

This is the output of the example.

Java LocalTime compare

The following example shows how to compare times.

JavaLocalTimeCompare.java
package com.zetcode;

import java.time.LocalTime;

public class JavaLocalTimeCompare {

    public static void main(String[] args) {
        
        LocalTime time1 = LocalTime.of(4, 23, 12);
        LocalTime time2 = LocalTime.of(8, 03, 50);
        LocalTime time3 = LocalTime.of(12, 47, 35);

        if (time1.compareTo(time2) == 0) {
            System.out.println("time1 and time2 are equal");
        } else {
            System.out.println("time1 and time2 are not equal");
        }

        if (time2.isBefore(time3)) {
            System.out.println("time2 comes before time3");
        } else {
            System.out.println("time2 does not come before time3");
        }

        if (time3.isAfter(time1)) {
            System.out.println("time3 comes after time1");
        } else {
            System.out.println("time3 does not come after time1");
        }
    }
}

The example compares times. We check if they are equal, if the come before or after another time.

if (time1.compareTo(time2) == 0) {

The compareTo() compares two local times.

if (time2.isBefore(time3)) {

The isBefore() checks if a time comes before another time.

if (time3.isAfter(time1)) {

The isAfter() checks if a time comes after another time.

time1 and time2 are not equal
time2 comes before time3
time3 comes after time1

This is the output.

Java LocalTime truncate

The LocalTime's truncatedTo() method returns a copy of a local time with the time truncated.

JavaLocaTimeTruncate.java
package com.zetcode;

import java.time.LocalTime;
import java.time.temporal.ChronoUnit;

public class JavaLocaTimeTruncate {

    public static void main(String[] args) {

        LocalTime now = LocalTime.now();

        System.out.println(now);
        System.out.println(now.truncatedTo(ChronoUnit.HALF_DAYS));
        System.out.println(now.truncatedTo(ChronoUnit.HOURS));
        System.out.println(now.truncatedTo(ChronoUnit.MINUTES));
        System.out.println(now.truncatedTo(ChronoUnit.SECONDS));
        System.out.println(now.truncatedTo(ChronoUnit.MICROS));
    }
}

The example uses truncatedTo() to truncate time to half days, hours, minutes, seconds, and micros.

11:27:56.309
00:00
11:00
11:27
11:27:56
11:27:56.309

This is the output.

In this tutorial, we have worked with Java LocalTime. You might also be interested in the related tutorials: Java tutorial, Java HashSet tutorial, Java TemporalAdjusters tutorial, Reading text files in Java, and Reading and writing ICO images in Java.