Question

Question 4 (10 points) How does Java handle constructors in inheritance? Please explain if there is any problem with the block of code below class People! private String name: public People(String name) { this.name = name; 3 class Student extends People { private String studentiD: public Student(String studentID) { this.studenti - studentID: 3 Format BIU ... Question 5 (10 points

Answer 1

In java, the constructor of base class with no argument gets automatically called in derived class constructor.

If we want to call the parameterized contructor of base class, then we can call it using super(parameter1,parameter2,....)

The base class constructor call must be the first line in derived class constructor.

The problem with the block of code given above is that the value for name is not initialised for the Student object.

For setting the value of name for student, the constructor must receive the name in its parameters and the base class constructor needs to be called using super.

The changed Student class would look like:

class Student extends People{
    private String studentID;

    public Student(String studentID,String name){
        super(name);
        this.studentID = studentID;
    }
}

Here we initialise the name value using super() and passing the value of name. This call to super() calls the base class constructor and initialises the value of name.