The naturalOrder() method of Comparator Interface in Java returns a comparator that use to compare Comparable objects in natural order. The returned comparator by this method is serializable and throws NullPointerException when comparing null.
Syntax:
static <T extends Comparable<T>>
Comparator<T> naturalOrder()
Parameters: This method accepts nothing.
Return value: This method returns a comparator that imposes the natural ordering on Comparable objects.
Below programs illustrate naturalOrder() method:
Program 1:
// Java program to demonstrate// Comparator.naturalOrder() method  import java.util.Arrays;import java.util.Comparator;import java.util.List;  public class GFG {    public static void main(String... args)    {          List<Integer> values            = Arrays.asList(212, 324,                            435, 566,                            133, 100, 121);          // naturalOrder is a static method        values.sort(Comparator.naturalOrder());          // print sorted number based on natural order        System.out.println(values);    }} |
The output printed on console of IDE is shown below.
Output:
Program 2:
// Java program to demonstrate// Comparator.naturalOrder() method  import java.util.Arrays;import java.util.Comparator;import java.util.List;  public class GFG {    public static void main(String... args)    {          List<String> stringList            = Arrays.asList("Aman", "Kajal",                            "Joyita", "Das");          System.out.println("Before sorting:");        stringList.forEach(System.out::println);          stringList.sort(Comparator.naturalOrder());        System.out.println("\nAfter sorting:");        stringList.forEach(System.out::println);    }} |
The output printed on console is shown below.
Output:
References: https://docs.oracle.com/javase/10/docs/api/java/util/Comparator.html#naturalOrder()
