isBefore() method of an Instant class checks if this instant timeline position is before the instant passed as parameter or not. If this instant timeline position is before the instant passed as a parameter then the method will return true else false. The comparison is based on the time-line position of the instants. Syntax:
public boolean isBefore(Instant otherInstant)
Parameter: This method takes a parameter otherInstant which is the other instant to compare to. It should not be null. Returns: This method returns true if this instant is before the specified instant. Exception: This method throws NullPointerException if otherInstant is null. Below programs illustrate the isBefore() method: Program 1:
Java
// Java program to demonstrate// Instant.isBefore() methodimport java.time.*;public class GFG { public static void main(String[] args) { // create a Instant object Instant instant1 = Instant.parse("2018-12-30T09:24:54.63Z"); // create other Instant Instant instant2 = Instant.parse("2018-12-31T01:34:00.63Z"); // print instances System.out.println("Instance 1: " + instant1); System.out.println("Instance 2: " + instant2); // check if instant1 is before instant2 // using isbefore() boolean value = instant1.isBefore(instant2); // print result System.out.println("Is Instant1 before Instant2: " + value); }} |
Instance 1: 2018-12-30T09:24:54.630Z Instance 2: 2018-12-31T01:34:00.630Z Is Instant1 before Instant2: true
Program 2:
Java
// Java program to demonstrate// Instant.isBefore() methodimport java.time.*;public class GFG { public static void main(String[] args) { // create a Instant object Instant instant1 = Instant.parse("2018-11-27T09:24:54.63Z"); // create other Instant Instant instant2 = Instant.now(); // print instances System.out.println("Instance 1: " + instant1); System.out.println("Instance 2: " + instant2); // check if instant1 is before instant2 // using isBefore() boolean value = instant1.isBefore(instant2); // print result System.out.println("Is Instant1 before Instant2: " + value); }} |
Instance 1: 2018-11-27T09:24:54.630Z Instance 2: 2018-11-27T04:55:36.127Z Is Instant1 before Instant2: false
Program 3: To show Exception thrown by isBefore()
Java
// Java program to demonstrate// Instant.isBefore() methodimport java.time.*;public class GFG { public static void main(String[] args) { // create a Instant object Instant instant1 = Instant.parse("2018-10-30T19:34:50.63Z"); // create other Instant Instant instant2 = null; try { // print instances System.out.println("Instance 1: " + instant1); System.out.println("Instance 2: " + instant2); // check if instant1 is before instant2 // using isBefore() boolean value = instant1.isBefore(instant2); } catch (Exception e) { // print result System.out.println("Exception: " + e); } }} |
Instance 1: 2018-10-30T19:34:50.630Z Instance 2: null Exception: java.lang.NullPointerException
References: https://docs.oracle.com/javase/10/docs/api/java/time/Instant.html#isBefore(java.time.Instant)
