Traverse through a HashSet in Java

Difficulty Level : Basic
Last Updated : 11 Dec, 2018

Note that HashSet elements are not ordered, so the traversed elements can be printed in any order.

Using an Iterator : The iterator() method is used to get an iterator over the elements in this set. The elements are returned in no particular order. Below is the java program to demonstrate it.

// Java program to demonstrate iteration over 
// HashSet using an iterator 
import java.util.*; 
  
class IterationDemo { 
    public static void main(String[] args) 
    { 
        HashSet<String> h = new HashSet<String>(); 
  
        // Adding elements into HashSet usind add() 
        h.add("Geeks"); 
        h.add("for"); 
        h.add("Geeks"); 
  
        // Iterating over hash set items 
        Iterator<String> i = h.iterator(); 
        while (i.hasNext()) 
            System.out.println(i.next()); 
    } 
} 

Output:

Geeks
for

Using for-each loop :

// Java program to demonstrate iteration over 
// HashSet using an Enhanced for-loop 
  
import java.util.*; 
  
class IterationDemo { 
    public static void main(String[] args) 
    { 
        // your code goes here 
        HashSet<String> h = new HashSet<String>(); 
  
        // Adding elements into HashSet usind add() 
        h.add("Geeks"); 
        h.add("for"); 
        h.add("Geeks"); 
  
        // Iterating over hash set items 
        for (String i : h)  
            System.out.println(i);         
    } 
} 

Output:

Geeks
for

Using forEach() method :
In Java 8 or above, we can iterate a List or Collection using forEach() method.

// Java program to demonstrate iteration over 
// HashSet using forEach() method 
  
import java.util.*; 
  
class IterationDemo { 
    public static void main(String[] args) 
    { 
        // your code goes here 
        HashSet<String> h = new HashSet<String>(); 
  
        // Adding elements into HashSet usind add() 
        h.add("Geeks"); 
        h.add("for"); 
        h.add("Geeks"); 
  
        // Iterating over hash set items 
        h.forEach(i -> System.out.println(i)); 
    } 
} 

Output:

Geeks
for

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