java.util.TreeSet.first() Method

Description

The first() method is used to return the first (lowest) element currently in this set.

Declaration

Following is the declaration for java.util.TreeSet.first() method.

public E first()

Parameters

• NA

Return Value

The method call returns the first (lowest) element currently in this set.

Exception

• NoSuchElementException--This exception is thrown if the set is empty.

Example

The following example shows the usage of java.util.TreeSet.first() method.

package com.tutorialspoint;

import java.util.TreeSet;

public class TreeSetDemo {
   public static void main(String[] args) {
     // creating a TreeSet 
     TreeSet <Integer>treeadd = new TreeSet<Integer>();
     
     // adding in the tree set
     treeadd.add(12);
     treeadd.add(11);
     treeadd.add(16);
     treeadd.add(15);
     
     // getting the first lowset element
     System.out.println("First lowest element: "+treeadd.first());   
   }    
}  

Let us compile and run the above program, this will produce the following result.

First lowest element: 11