This examples explains the basic concept of creating a Parent or Super Class and later a child class extends the behavior of the super or parent class.
 

//java Sublcass_Constructor_1.java
public class Sublcass_Constructor_1
{
enum Days{Monday, Tuesday};
public static void main(String[] args) {
// TODO Auto-generated method stub
Achild child = new Achild();
}
}

// a parent class with a constructor
class Aparent
{
public Aparent()
{
System.out.println("A Parent constructor ");
}

}

// an extended child class with a constructor
class Achild extends Aparent
{
public Achild()
{
System.out.println("A Child Constructor");
}

}