What is printed?

public class Inherit
{

class Figure
{
void display( )
{
System.out.println("Figure");
}
}

class Rectangle extends Figure
{
void display( )
{
System.out.println("Rectangle");
}
}

class Box extends Rectangle
{
void display( )
{
System.out.println("Box");
}
}

Inherit( )
{
Figure f = new Figure( );
Rectangle r = new Rectangle( );
Box b = new Box( );
f.display( );
f = r;
((Figure) f).display( );
f = (Figure) b;
f.display( );
}

public static void main(String[ ] args)
{
new Inherit( );
}
}
A) Figure
Rectangle
Box
B) Figure
Figure
Figure
C) Figure
Rectangle
Figure
D) Rectangle
Figure
E) none of the above

Question

What is printed?

public class Inherit
	{

class Figure
		{
			void display( )
			{
				System.out.println("Figure");
			}
		}

class Rectangle extends Figure
		{
			void display( )
			{
				System.out.println("Rectangle");
			}
		}

class Box extends Rectangle
		{
			void display( )
			{
				System.out.println("Box");
			}
		}

Inherit( )
		{
			Figure f = new Figure( );
			Rectangle r = new Rectangle( );
			Box b = new Box( );
			f.display( );
			f = r;
			((Figure) f).display( );
			f = (Figure) b;
			f.display( );
		}

public static void main(String[ ] args)
		{
			new Inherit( );
		}
	} 
A) Figure
Rectangle
Box 
B) Figure
Figure
Figure 
C) Figure
Rectangle
Figure 
D) Rectangle
Figure 
E) none of the above

Quizplus · Accepted Answer

A) f, r, and b all are polymorphic reference variables. Checking to see which instances of what classes are present when the display( ) methods are invoked you'll see that three lines of output are produce, and that answer A shows the correct output.

What Is Printed? Public Class Inherit