The first() method of SortedSet interface in Java is used toReturns the first i.e., the lowest element currently in this set.
Syntax:
E first()
Where, E is the type of element maintained by this Set.
Parameters: This function does not accepts any parameter.
Return Value: It returns the first or the lowest element currently in the set.
Exceptions: It throws NoSuchElementException, if the set is empty.
Below programs illustrate the above method:
Program 1:
Java
// A Java program to demonstrate// working of SortedSetimport java.util.SortedSet;import java.util.TreeSet;public class Main { public static void main(String[] args) { // Create a TreeSet and inserting elements SortedSet<Integer> s = new TreeSet<>(); // Adding Element to SortedSet s.add(1); s.add(5); s.add(2); s.add(3); s.add(9); // Returning the lowest element from set System.out.print("Lowest element in set is : " + s.first()); }} |
Output:
Lowest element in set is : 1
Program 2:
Java
// Program to illustrate the first()// method of SortedSet interfaceimport java.util.SortedSet;import java.util.TreeSet;public class GFG { public static void main(String args[]) { // Create an empty SortedSet SortedSet<Integer> s = new TreeSet<>(); // Trying to access element from // empty set try { s.first(); } catch (Exception e) { // throws NoSuchElementException System.out.println("Exception: " + e); } }} |
Output:
Exception: java.util.NoSuchElementException
Reference: https://docs.oracle.com/javase/10/docs/api/java/util/SortedSet.html#first()
