— Scott McNealy, Sun Microsystems Chairman, President and ceo

public Boop() {
}
public Boop(int i) {
size = i;
}
public Boop(int i) {
size = i;
super();
}
These are OK because 
the compiler will put a 
call to super() in as the 
first statement.
BAD!! This won’t compile! 
You can’t explicitly put 
the call to super() below 
anything else.
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constructors and 
gc
you are here
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Superclass constructors with arguments
What if the superclass constructor has arguments? Can you pass something in to 
the super() call? Of course. If you couldn’t, you’d never be able to extend a class 
that didn’t have a no-arg constructor. Imagine this scenario: all animals have a 
name. There’s a getName() method in class Animal that returns the value of the 
name instance variable. The instance variable is marked private, but the subclass 
(in this case, Hippo) inherits the getName() method. So here’s the problem: 
Hippo has a getName() method (through inheritance), but does not have the name 
instance variable. Hippo has to depend on the Animal part of himself to keep the 
name instance variable, and return it when someone calls getName() on a Hippo 
object. But... how does the Animal part get the name? The only reference Hippo 
has to the Animal part of himself is through super(), so that’s the place where 
Hippo sends the Hippo’s name up to the Animal part of himself, so that the 
Animal part can store it in the private name instance variable.
Animal
private String name
Animal(String n)
String getName()
Hippo
Hippo(String n)
[other Hippo-spe-
cific methods]