Advanced quizzes – Java final classes and variables

The following Java exercise(s) are designed for advanced level developers. If the level is too hard, then I recommend to select an easier one or you might consider reading my article about this topic, which offers a theoretical explanation including more exercises. Read More: Java Final Classes And Methods

Article: Java final classes and methods
Quizzes: Beginner Intermediate Advanced

final-classes-red

Quiz 1: Final classes and variables in Java

What appears in the standard output when this program is invoked?

public class Super {

	final int x = 2;
	int y = 3;

	Super() {
		y ++ ;
		System.out.print("-x" + method());
	}
	int method(){
		return x + y;
	}
	int method(int i){
		return y + x + i;
	}
}

class Final extends Super {

	final int x = 5;
	int y = 6;

	Final() {
		y ++ ;
		System.out.print("-x" + method(3));
	}
	final int method(){
		System.out.print("-x" + y + "-x" + (x + 1));
		return y + 3;
	}
	final int method(int x){
		return y + super.x + x;
	}
	public static void main(String[] args){
		Final f = new Final();
	}
}

Select the correct answer.

a. Illegal at compile time.

b. Illegal at run time.

c. This code writes "-x6-x12" to the standard output.

d. This code writes "-x0-x6-x3-x12" to the standard output.

e. This code writes "-x5-x13" to the standard output.

f. This code writes "-x6-x6-x9-x12" to the standard output.

g. This code writes "-x0-x6-x9-x12" to the standard output.

h. This code writes "null" to the standard output.

i. This code writes nothing to the standard output.