This is an example of how to check for an element existence in a HashSet. Checking if an element exists in a HashSet implies that you should:
- Create a new HashSet.
- Populate the hashSet with elements, using
add(E e)API method of HashSet. - Invoke
contains(Object value)API method of HashSet, with a specified element as parameter. The method returns true if the element exists in the hashSet and false otherwise.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core;
import java.util.HashSet;
public class ElementExistsHashSet {
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");
// boolean contains(Object value) method returns true if the HashSet contains the value, otherwise false.
boolean exists = hashSet.contains("element_2");
System.out.println("element_2 exists in HashSet ? : " + exists);
}
}
Output:
element_2 exists in HashSet ? : true
This was an example of how to check for an element existence in a HashSet in Java.
