The higher(E e) method of java.util.concurrent.ConcurrentSkipListSet is an in-built function in Java which returns the least element in this set strictly greater than the given element, or null if there is no such element.
Syntax:
public E higher(E e)
Parameter: The function accepts a single parameter e i.e the value to match
Return Value: The function returns the least element greater than e, or null if there is no such element.
Exception: The function throws the following exceptions:
Below programs illustrate the ConcurrentSkipListSet.higher(E e) method:
Program 1:
// Java program to demonstrate higher()// method of ConcurrentSkipListSet  import java.util.concurrent.*;  class ConcurrentSkipListSetHigherExample1 {    public static void main(String[] args)    {        // Creating a set object        ConcurrentSkipListSet<Integer>            Lset = new ConcurrentSkipListSet<Integer>();          // Adding elements to this set        for (int i = 10; i <= 50; i += 10)            Lset.add(i);          // Finding higher of 20 in the set        System.out.println("The higher of 20 in the set: "                           + Lset.higher(20));          // Finding higher of 39 in the set        System.out.println("The higher of 39 in the set: "                           + Lset.higher(39));          // Finding higher of 50 in the set        System.out.println("The higher of 50 in the set: "                           + Lset.higher(50));    }} |
Output:
The higher of 20 in the set: 30 The higher of 39 in the set: 40 The higher of 50 in the set: null
Program 2: Program to show NullPointerException in higher().
// Java program to demonstrate higher()// method of ConcurrentSkipListSet  import java.util.concurrent.*;  class ConcurrentSkipListSetHigherExample1 {    public static void main(String[] args)    {        // Creating a set object        ConcurrentSkipListSet<Integer>            Lset = new ConcurrentSkipListSet<Integer>();          // Adding elements to this set        for (int i = 10; i <= 50; i += 10)            Lset.add(i);          try {            // Trying to find higher of "null" in the set            System.out.println("The higher of null in the set: "                               + Lset.higher(null));        }        catch (Exception e) {            System.out.println("Exception: " + e);        }    }} |
Output:
Exception: java.lang.NullPointerException
Reference:
https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentSkipListSet.html#higher-E-
