Example Code Ch 09-5
Consider the following class definition:
public class AClass
{
protected int x;
protected int y;
public AClass(int a, int b)
{
x = a;
y = b;
}
public int addEm()
{
return x + y;
}
public void changeEm()
{
x++;
y--;
}
public String toString()
{
return "" + x + " " + y;
}
}
-Refer to Example Code Ch 09-5: Which of the following would best redefine the toString method for BClass?
A) public String toString(int z)
{
Return " " + x + " " + y + " " + z;
}
B) public String toString()
{
Return super.toString();
}
C) public String toString()
{
Return super.toString() + " " + z;
}
D) public String toString()
{
Return super.toString()+" " x+" "+y+" "+z;
}
E) public String toString()
{
Return " " + x + " + y + " " + z;
}

Question

Quizplus · Accepted Answer

Option A includes an additional parameter that is not in the original definition and would cause a compilation error. 
Option B simply returns the output of the superclass's toString method, and does not redefine it for the subclass. 
Option D is missing a plus sign between the quote and x, which would also cause a compilation error. 
Option E is missing quotes around the variables x and y, which would result in the output being " x + y " instead of the concatenated values of x and y. Option C, on the other hand, includes the addition of a new variable z to the output of the superclass's toString method, which is a valid and appropriate way to redefine the method in the subclass.