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Java Tutorial : Implementing an Interface

Person.java

public interface Person
{
    void walk();
}

Student.java

public class Student implements Person
{

    @Override
    public void walk()
    {
        System.out.println("Student walks slowly");

    }

}

public class InterfaceTest
{

    public static void main(String[] args)
    {
        Person personRef = new Student();
        personRef.walk();
    }

}