With Java 8, a brand new Date-Time API is delivered to cowl the subsequent drawbacks of antique date-time API.
Java 8 introduces a brand new date-time API beneath the bundle java.time. Following are a number of the vital instructions delivered in java.time bundle.
LocalDate/LocalTime and LocalDateTime instructions simplify the improvement wherein time zones aren't required. Let's see them in action.
Create the subsequent java software the usage of any editor of your preference in, say, C:> JAVA.
Java8Tester.java
import java.time.LocalDate; import java.time.LocalTime; import java.time.LocalDateTime; import java.time.Month; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testLocalDateTime(); } public void testLocalDateTime() { // Get the current date and time LocalDateTime currentTime = LocalDateTime.now(); System.out.println("Current DateTime: " + currentTime); LocalDate date1 = currentTime.toLocalDate(); System.out.println("date1: " + date1); Month month = currentTime.getMonth() int day = currentTime.getDayOfMonth(); int seconds = currentTime.getSecond(); System.out.println("Month: " + month +"day: " + day +"seconds: " + seconds); LocalDateTime date2 = currentTime.withDayOfMonth(10).withYear(2012); System.out.println("date2: " + date2); //12 december 2014 LocalDate date3 = LocalDate.of(2014, Month.DECEMBER, 12); System.out.println("date3: " + date3); //22 hour 15 minutes LocalTime date4 = LocalTime.of(22, 15); System.out.println("date4: " + date4); //parse a string LocalTime date5 = LocalTime.parse("20:15:30"); System.out.println("date5: " + date5); } }
Assemble the Class Using javac Compiler as given below:
C:\JAVA>javac Java8Tester.java
C:\JAVA>java Java8Tester
Current DateTime: 2014-12-09T11:00:45.457 date1: 2014-12-09 Month: DECEMBERday: 9seconds: 45 date2: 2012-12-10T11:00:45.457 date3: 2014-12-12 date4: 22:15 date5: 20:15:30
Zoned date-time API is to be used when a zone is to be considered. And allow us to view them in working.
Create the subsequent Java program using any editor of your choice in, say, C:\> JAVA.
Java8Tester.java
import java.time.ZonedDateTime; import java.time.ZoneId; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testZonedDateTime(); } public void testZonedDateTime() { // Get the current date and time ZonedDateTime date1 = ZonedDateTime.parse("2007-12-03T10:15:30+05:30[Asia/Karachi]"); System.out.println("date1: " + date1); ZoneId id = ZoneId.of("Europe/Paris"); System.out.println("ZoneId: " + id); ZoneId currentZone = ZoneId.systemDefault(); System.out.println("CurrentZone: " + currentZone); } }
Assemble the whole class with javac compiler as follows:
C:\JAVA>javac Java8Tester.java
C:\JAVA>java Java8Tester
date1: 2007-12-03T10:15:30+05:00[Asia/Karachi] ZoneId: Europe/Paris CurrentZone: Etc/UTC
java.time.temporal.ChronoUnit enum is added in Java 8 to exchange the integer values utilized in the old API to represent the day, month, etc. And allowing us to view them while working.
Create the subsequent Java program using any editor of your choice in, say, C:\> JAVA
Java8Tester.java
import java.time.LocalDate; import java.time.temporal.ChronoUnit; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testChromoUnits(); } public void testChromoUnits() { //Get the current date LocalDate today = LocalDate.now(); System.out.println("Current date: " + today); //add 1 week to the current date LocalDate nextWeek = today.plus(1, ChronoUnit.WEEKS); System.out.println("Next week: " + nextWeek); //add 1 month to the current date LocalDate nextMonth = today.plus(1, ChronoUnit.MONTHS); System.out.println("Next month: " + nextMonth); //add 1 year to the current date LocalDate nextYear = today.plus(1, ChronoUnit.YEARS); System.out.println("Next year: " + nextYear); //add 10 years to the current date LocalDate nextDecade = today.plus(1, ChronoUnit.DECADES); System.out.println("Date after ten year: " + nextDecade); } }
Assemble the class using the javac compiler as follows:
C:\JAVA>javac Java8Tester.java
C:\JAVA>java Java8Tester
Current date: 2014-12-10 Next week: 2014-12-17 Next month: 2015-01-10 Next year: 2015-12-10 Date after ten year: 2024-12-10
In Java 8 we have two new specified classes are introduced to allocate with the time differences
Produce the given Java program using the editor of your choice in, say, C:\> JAVA.
Java8Tester.java
import java.time.temporal.ChronoUnit; import java.time.LocalDate; import java.time.LocalTime; import java.time.Duration; import java.time.Period; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testPeriod(); java8tester.testDuration(); } public void testPeriod() { //Get the current date LocalDate date1 = LocalDate.now(); System.out.println("Current date: " + date1); //add 1 month to the current date LocalDate date2 = date1.plus(1, ChronoUnit.MONTHS); System.out.println("Next month: " + date2); Period period = Period.between(date2, date1); System.out.println("Period: " + period); } public void testDuration() { LocalTime time1 = LocalTime.now(); Duration twoHours = Duration.ofHours(2); LocalTime time2 = time1.plus(twoHours); Duration duration = Duration.between(time1, time2); System.out.println("Duration: " + duration); } }
Assemble your class with javac compiler as given below:
C:\JAVA>javac Java8Tester.java
Now, Run the Java8Tester as given below:
C:\JAVA>java Java8Tester
It must Produce the output like this:
Current date: 2014-12-10 Next month: 2015-01-10 Period: P-1M Duration: PT2H
Temporal Adjuster is employed to perform the date mathematics. For instance, take the "Second Saturday of the Month" or "Next Tuesday". And allow us to view them while working.
Create the subsequent Java program using any editor of your choice in, say, C:\> JAVA.
Java8Tester.java import java.time.LocalDate; import java.time.temporal.TemporalAdjusters; import java.time.DayOfWeek; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testAdjusters(); } public void testAdjusters() { //Get the current date LocalDate date1 = LocalDate.now(); System.out.println("Current date: " + date1); //get the next tuesday LocalDate nextTuesday = date1.with(TemporalAdjusters.next(DayOfWeek.TUESDAY)); System.out.println("Next Tuesday on : " + nextTuesday); //get the second saturday of next month LocalDate firstInYear = LocalDate.of(date1.getYear(),date1.getMonth(), 1); LocalDate secondSaturday = firstInYear.with(TemporalAdjusters.nextOrSame( DayOfWeek.SATURDAY)).with(TemporalAdjusters.next(DayOfWeek.SATURDAY)); System.out.println("Second Saturday on : " + secondSaturday); } }
Assemble the class using the javac compiler as follow:
C:\JAVA>javac Java8Tester.java
C:\JAVA>java Java8Tester
Current date: 2014-12-10 Next Tuesday on : 2014-12-16 Second Saturday on : 2014-12-13
A constant() method is added to the first Date and Calendar objects, which may be wont to convert them to the new Date-Time API. Use an ofInstant(Insant,ZoneId) method to urge a LocalDateTime or ZonedDateTime object. And allow us to view them working.
Create the subsequent Java program using any editor of your choice in, say, C:\> JAVA.
Java8Tester.java
import java.time.LocalDateTime; import java.time.ZonedDateTime; import java.util.Date; import java.time.Instant; import java.time.ZoneId; public class Java8Tester { public static void main(String args[]) { Java8Tester java8tester = new Java8Tester(); java8tester.testBackwardCompatability(); } public void testBackwardCompatability() { //Get the current date Date currentDate = new Date(); System.out.println("Current date: " + currentDate); //Get the instant of current date in terms of milliseconds Instant now = currentDate.toInstant(); ZoneId currentZone = ZoneId.systemDefault(); LocalDateTime localDateTime = LocalDateTime.ofInstant(now, currentZone); System.out.println("Local date: " + localDateTime); ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(now, currentZone); System.out.println("Zoned date: " + zonedDateTime); } }
Assemble the class with the help of Javac Compiler as given below