Check if a particular element exists in Java HashSet Example

1.Basic java example program to check particular element is exists in hashset

• boolean contains(Object o)   This method Returns true if this set contains the specified element

1. package com.checkelementhashset;
2.  
3. import java.util.HashSet;
4. import java.util.Iterator;
5.  
6. public class HashsetExample{
7.  
8. public static void main(String[] args) {
9.   
10. //create object of HashSet
11.  HashSet<Integer> hashSet = new HashSet();
12.        
13.  //add elements to HashSet object
14.  hashSet.add(1);
15.  hashSet.add(2);
16.  hashSet.add(3);
17.  hashSet.add(4);
18.  hashSet.add(5);
19.      
20.  /*
21.  To check whether a particular value exists in HashSetwe need to use
22.   boolean contains(Object value) method of HashSet class.
23.  this method returns true if the HashSet contains the value, otherwise returns false.
24.  */
25.        
26.         boolean isExists = hashSet.contains(5);
27.         System.out.println("5 exists in HashSet ? : " + isExists);    
28.  
29. 
    
30.  
31. Iterator it=hashSet.iterator();
32.              
33. while(it.hasNext()){
34. System.out.println(it.next());
35.                      
36. }   
37.  
38. }
39.  
40. }
     

Output:

1. 3 exists in HashSet ? : true
2. 1
3. 2
4. 3
5. 4
6. 5