Problem with the code

[Parul Sweetie]

1. class Person{
2. String name="No Name";
3. public Person(String nm){name=nm;}
4. }
5. class Employee extends Person{
6. String id="0000";
7. public Employee(String emplId){id=emplId;}
8. }
9. public class EmployeeTest{
10. public static void main(String args[]){
11. Employee e=new Employee("4321");
12. System.out.println(e.id);
13. }
14. }


Guys please tell me what's the problem in line 7. Thanks in advance.

[Matthew Brown]

Have you tried it? What error message did you get?

(Think about what constructors get called)

[Dan Drillich]

Hi Parul,

Do you have, by any chance, the study guide by Kathy Sierra and Bert Bates?

If so, please have a look at the section - "Determine whether a Default Constructor Will Be created".

Regards,
Dan

[Himai Minh]

One way you can do is:

 class Person{
    String name="No Name";
  public Person(String nm){name=nm;}

 //add this default constructor
  public Person (){

  }
 }
  class Employee extends Person{
     String id="0000";
    public Employee(String emplId){
        super();      //implicity this super is called.
        id=emplId;
    }
}
  public class EmployeeTest{
   public static void main(String args[]){
     Employee e=new Employee("4321");
    System.out.println(e.id);
    }
   }

Since Employee is a child of Person. Its contructor will call super() implicity. The super() will call the default contructor of Person. Since your original code does not have a default contructor of Person, it won't compile.
If you define a contructor with some arguments, you may want to define a non-argument contructor as well. It is because the child class may call super().

[Parul Sweetie]

Thanks everybody....