Click here to watch in Youtube :
https://www.youtube.com/watch?v=RTC-WPdjweE&list=UUhwKlOVR041tngjerWxVccw

Employee.java

public class Employee
{

    private String name;
    private int    age;
    private int    salary;

    public Employee( String name, int age, int salary )
    {
        super();
        this.name = name;
        this.age = age;
        this.salary = salary;
    }

    public String getName()
    {
        return name;
    }

    public void setName( String name )
    {
        this.name = name;
    }

    public int getAge()
    {
        return age;
    }

    public void setAge( int age )
    {
        this.age = age;
    }

    public int getSalary()
    {
        return salary;
    }

    public void setSalary( int salary )
    {
        this.salary = salary;
    }

    @Override
    public String toString()
    {
        return "Employee [name=" + name + ", age=" + age + ", salary=" + salary
                + "]";
    }

}

import java.util.HashSet;

/*
 * Storing user-defined class objects.
 */
public class HashSetExample
{
    public static void main(String[] args)
    {
        HashSet<Employee> hashSet = new HashSet<Employee>();

        Employee john = new Employee("John", 32, 40000);
        Employee david = new Employee("David", 42, 80000);
        Employee peter = new Employee("Peter", 52, 150000);

        hashSet.add(john);
        hashSet.add(david);
        hashSet.add(peter);

        System.out.println("hashSet : " + hashSet + "\n");

        /*
         * Using for each loop getting each employee object from the hashSet
         */
        for (Employee employee : hashSet)
        {
            System.out.println("-------------------------------------");
            System.out.println(employee.toString());
            System.out.println("Name : " + employee.getName());
            System.out.println("Age : " + employee.getAge());
            System.out.println("Salary : " + employee.getSalary());
        }

    }
}