Calling super()

Question

When do you call super() in Java? I see it in some constructors of the derived class, but isn\'t the constructors for each of the parent class called automatically? Why woul

Answer 1

Although super() does nothing functionally for the compiler (the superclass default constructor is called automatically), it certainly does a lot for me. It says to me: "Do not remove the empty constructor. It's there for a reason".

A perfect example is where you create Spring managed beans or JPA Entities and you've created a parameterized constructor.

@Entity
public class Portfolio {

    ...

    public Portfolio() {
        super(); // This says to me: DON'T DELETE!
    }

    /**
    *  Because there is now a parameterised constructor (me), 
    *  the default constructor no longer exists. This means
    *  that for this example, you need an empty constructor in place (above) 
    **/
    public Portfolio(String name) {
        this.name = name;
    }
}