Multiple choice technology programming languages

  1. class Building { 4. Building() { System.out.print("b "); } 5. Building(String name) { 6. this(); System.out.print("bn " + name); 7. } 8. } 9. public class House extends Building { 10. House() { System.out.print("h "); } 11. House(String name) { 12. this(); System.out.print("hn " + name); 13. } 14. public static void main(String[] args) { new House("x "); } 15. }

  1. h hn x

  2. hn x h

  3. b h hn x

  4. b hn x h

  5. bn x h hn x
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The House(String) constructor calls this() to invoke House(), which implicitly calls super() to execute Building(). Building() prints 'b ', then House() prints 'h ', and finally House(String) prints 'hn x'. The complete output is 'b h hn x'.

AI explanation

To understand the given code and determine the output, let's analyze each part of it step by step:

  1. The code starts with the definition of a class Building.
  2. The Building class has two constructors: Building() and Building(String name).
  3. The first constructor Building() prints "b ".
  4. The second constructor Building(String name) calls the first constructor using this(), and then prints "bn " followed by the value of name.
  5. Next, there is a class House that extends the Building class.
  6. The House class has two constructors: House() and House(String name).
  7. The first constructor House() prints "h ".
  8. The second constructor House(String name) calls the first constructor using this(), and then prints "hn " followed by the value of name.
  9. Finally, the main method of the House class creates a new House object with the value "x " as the argument.

Now, let's go through the options to determine the correct output:

Option A) h hn x

This option is incorrect. It suggests that the output will be "h hn x". However, it doesn't consider the constructors of the Building class.

Option B) hn x h

This option is incorrect. It suggests that the output will be "hn x h". However, it doesn't consider the constructors of the Building class.

Option C) b h hn x

This option is correct. As per the given code, the output will be "b h hn x". The House constructor calls the Building constructor using this(), which in turn calls the Building() constructor, printing "b ". Then, the House constructor prints "h ", followed by "hn " and the value "x ".

Option D) b hn x h

This option is incorrect. It suggests that the output will be "b hn x h". However, it doesn't consider the order of constructor calls.

Option E) bn x h hn x

This option is incorrect. It suggests that the output will be "bn x h hn x". However, it doesn't consider the order of constructor calls.

Therefore, the correct answer is option C) b h hn x.

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