Pre-Defined Enum

Overview of built-in Enum provided in Java.

ChronoUnit

It is an enum in the java.time.temporal package in Java, introduced in Java 8 as part of the java.time package for date and time manipulation. It represents units of time, such as days, hours, minutes, seconds, etc., and provides a way to perform date and time arithmetic. ChronoUnit constants can be used along with methods like plus and minus to add or subtract a specified amount of time from a date-time object.

Here are some commonly used ChronoUnit constants:

• NANOS: Nanoseconds

• MICROS: Microseconds

• MILLIS: Milliseconds

• SECONDS: Seconds

• MINUTES: Minutes

• HOURS: Hours

• DAYS: Days

• WEEKS: Weeks

• MONTHS: Months

• YEARS: Years

• DECADES: Decades

• CENTURIES: Centuries

• MILLENNIA: Millennia

• ERAS: Eras

ZonedDateTime currentDateTime = ZonedDateTime.now();
ZonedDateTime futureDateTime = currentDateTime.plus(3, ChronoUnit.HOURS);
ZonedDateTime pastDateTime = currentDateTime.minus(1, ChronoUnit.DAYS);