How to check if HashSet contains an element

In this post we will see examples on how to check if Hashset contains an element/object.

For this we will use the boolean contains(Object o) method.

Example : Check if HashSet contains the Element/Object

package com.kscodes.sampleproject;

import java.util.HashSet;
import java.util.Set;

public class HashSetConatinsExample {

	public static void main(String[] args) {

		Set<String> hashSet = new HashSet<>();

		hashSet.add("Java");
		hashSet.add("Spring");
		hashSet.add("Hibernate");
		hashSet.add("JavaScript");

		System.out.println("Does HashSet contain - 'JQuery' :: "
				+ hashSet.contains("JQuery"));

		System.out.println("Does HashSet contain - 'Java' :: "
				+ hashSet.contains("Java"));

	}
}

package com.kscodes.sampleproject;

import java.util.HashSet;

import java.util.Set;

public class HashSetConatinsExample {

public static void main(String[] args) {

Set<String> hashSet = new HashSet<>();

hashSet.add("Java");

hashSet.add("Spring");

hashSet.add("Hibernate");

hashSet.add("JavaScript");

System.out.println("Does HashSet contain - 'JQuery' :: "

+ hashSet.contains("JQuery"));

System.out.println("Does HashSet contain - 'Java' :: "

+ hashSet.contains("Java"));

}

Output

Does HashSet contain - 'JQuery' :: false
Does HashSet contain - 'Java' :: true

1 2	Does HashSet contain - 'JQuery' :: false Does HashSet contain - 'Java' :: true

Reference

1. HashSet contains method