In this example we shall show you how to remove an element from a HashSet if it exists in the HashSet. To remove an element from a HashSet one should perform the following steps:
- Create a new HashSet.
- Populate the HashSet with elements, using
add(E e)API method of HashSet. - Invoke
remove(Object o)API method of HashSet, with the element to be removed as parameter. The method removes the specified element from this set if it is present and returns true. If the element does not exist in the set it returns false,
as described in the code snippet below.
package com.javacodegeeks.snippets.core;
import java.util.HashSet;
public class RemoveElementHashSet {
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");
System.out.println("HashSet contents : " + hashSet);
// boolean remove(Object o) method removes the specific object from the HashSet if present and returns true, false otherwise
boolean removed = hashSet.remove("element_2");
System.out.println("HashSet contents after removal of element_2 : " + hashSet);
}
}
Output:
HashSet contents : [element_1, element_2, element_3]
HashSet contents after removal of element_2 : [element_1, element_3]
This was an example of how to remove an element from a HashSet in Java.
