In this example we shall show you how to get theHashSet size, that is the number of all the elements that the hashSet contains. To get the HashSet size one should perform the following steps:

• Create a newHashSet.
• Populate the hashSet with elements, usingadd(E e) API method of HashSet.
• Invokesize() API method of HashSet. The method returns the int number of the elements existing in the HashSet.
• We can remove an element from the hashSet, withremove(Object o) API method and then invokesize() method again, to check if the size is smaller after removing an element from the set,

as described in the code snippet below.

package com.javacodegeeks.snippets.core; import java.util.HashSet; public class HashSetSizeExample {   public static void main(String[] args) {     // Create a HashSet and populate it with elements    HashSet hashSet = new HashSet();    hashSet.add("element_1");    hashSet.add("element_2");    hashSet.add("element_3");     // int size() method returns the number of elements in the HashSet       System.out.println("Size of HashSet : " + hashSet.size());     // Remove one element from the HashSet using remove method    hashSet.remove("element_2");    System.out.println("Size of HashSet : " + hashSet.size());  }}

Output:

Size of HashSet : 3Size of HashSet : 2

 
This was an example of how to get the HashSet size in Java.

Do you want to know how to develop your skillset to become aJava Rockstar?

Subscribe to our newsletter to start Rockingright now!

To get you started we give you our best selling eBooks forFREE!

1. JPA Mini Book

2. JVM Troubleshooting Guide

3. JUnit Tutorial for Unit Testing

4. Java Annotations Tutorial

5. Java Interview Questions

6. Spring Interview Questions

7. Android UI Design

and many more ....

I agree to theTerms andPrivacy Policy

Sign up

Thank you!

We will contact you soon.