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Inner Classes - Programming

Q1:

What will be the output of the program? 
public class HorseTest 
{
    public static void main (String [] args) 
    {
        class Horse 
        {
            public String name; /* Line 7 */
            public Horse(String s) 
            {
                name = s;
            }
        } /* class Horse ends */
        
        Object obj = new Horse('Zippo'); /* Line 13 */
        Horse h = (Horse) obj; /* Line 14 */
        System.out.println(h.name);
    }
} /* class HorseTest ends */

A An exception occurs at runtime at line 10.

B It prints "Zippo".

C Compilation fails because of an error on line 7.

D Compilation fails because of an error on line 13.

ANS:A - An exception occurs at runtime at line 10.

The code in the HorseTest class is perfectly legal. Line 13 creates an instance of the method-local inner class Horse, using a reference variable declared as type Object. Line 14 casts the Horse object to a Horse reference variable, which allows line 15 to compile. If line 14 were removed, the HorseTest code would not compile, because class Object does not have a name variable.