Creating a HashSet and Adding New Elements to It

This example shows how to create a HashSet using the HashSet() constructor, and add new elements to it using the add() method.

Creating a HashSet and Adding New Elements to It

import java.util.HashSet; import java.util.Set; public class CreateHashSetExample { public static void main(String[] args) { // Creating a HashSet Set<String> daysOfWeek = new HashSet<>(); // Adding new elements to the HashSet daysOfWeek.add("Monday"); daysOfWeek.add("Tuesday"); daysOfWeek.add("Wednesday"); daysOfWeek.add("Thursday"); daysOfWeek.add("Friday"); daysOfWeek.add("Saturday"); daysOfWeek.add("Sunday"); // Adding duplicate elements will be ignored daysOfWeek.add("Monday"); System.out.println(daysOfWeek); } } 
# Output [Monday, Thursday, Friday, Sunday, Wednesday, Tuesday, Saturday]

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