The compareTo() method of LocalDateTime class in Java is used to compare this date-time to the date-time passed as the parameter.
Syntax:
public int compareTo(ChronoLocalDateTime anotherDate)
Parameter: This method accepts a parameter anotherDate which specifies the other date-time to be compare to. It should not be null.
Returns: The function returns an integer value which is the comparator value after comparison.
Below programs illustrate the LocalDateTime.compareTo() method:
Program 1:
// Program to illustrate the compareTo() method  import java.util.*;import java.time.*;  public class GfG {    public static void main(String[] args)    {        // Parses the date        LocalDateTime dt1            = LocalDateTime                  .parse("2018-11-03T12:45:30");          // Prints the date        System.out.println("Date 1: " + dt1);          // Parses the date        LocalDateTime dt2            = LocalDateTime                  .parse("2015-01-05T12:45:30");          // Prints the date        System.out.println("Date 2: " + dt2);          // Compares the date        System.out.println("After comparison: "                           + dt2.compareTo(dt1));    }} |
Output:
Date 1: 2018-11-03T12:45:30 Date 2: 2015-01-05T12:45:30 After comparison: -3
Program 2:
// Program to illustrate the compareTo() method  import java.util.*;import java.time.*;  public class GfG {    public static void main(String[] args)    {        // Parses the date        LocalDateTime dt1            = LocalDateTime                  .parse("2010-12-05T12:50:30");          // Prints the date        System.out.println("Date 1: " + dt1);          // Parses the date        LocalDateTime dt2            = LocalDateTime                  .parse("2012-05-10T12:50:30");          // Prints the date        System.out.println("Date 2: " + dt2);          // Compares the date        System.out.println("After comparison: "                           + dt2.compareTo(dt1));    }} |
Output:
Date 1: 2010-12-05T12:50:30 Date 2: 2012-05-10T12:50:30 After comparison: 2
