Showing Revision 4 created 05/25/2016 by Udacity Robot.

1. Title:
   The Quiz Hierarchy - Intro to Java Programming
2. Description:

3. 0 0:00 - 0:03
   And the car hierarchy you've just seen, makes it easy to understand the
4. 3127 0:03 - 0:06
   concepts of super and sub classes but it doesn't make for a very interesting
5. 6466 0:06 - 0:12
   implementation, instead lets look at quizzes. In a quiz, you can have different
6. 12044 0:12 - 0:18
   kinds of questions so it's natural to have a super class question. And then,
7. 17808 0:18 - 0:22
   you may have various sub classes. Maybe a question where you need to fill in a
8. 21915 0:22 - 0:25
   missing word, or a question where you're given a bunch of choices, or one where
9. 25490 0:25 - 0:29
   you've to supply a number, but it might be okay if it's not exactly the right
10. 28900 0:29 - 0:36
    answer. A numeric question might take round off into account. And so on. You
11. 36196 0:36 - 0:41
    could even think that there is a, sub-class of choice question. I'll call it a
12. 41494 0:41 - 0:45
    Multi Choice Question, you know, one of those where you need to supply all of
13. 44896 0:45 - 0:51
    the choices that are correct. What do our questions have in common? They all
14. 50594 0:51 - 0:54
    need to be able to display themselves, and the display may be as simple as
15. 54314 0:54 - 1:01
    showing the question text, or it might have to have a list of choices. Or an
16. 60690 1:01 - 1:04
    underscore at the right place for filling in a word, and also any question
17. 64045 1:04 - 1:09
    needs to be able to check its answer. That might be a string comparison or a
18. 69232 1:09 - 1:16
    number comparison that's, or a number comparison after some accuracy. So the
19. 75820 1:16 - 1:20
    idea is that, the super-class question will give reasonable implementations of
20. 80308 1:20 - 1:25
    these methods, and the sub-classes can modify them if they don't work for the
21. 84532 1:25 - 1:31
    context of the sub-classes. I've implemented the question class for you, and
22. 90504 1:31 - 1:34
    here is a programming problem that's designed to make you familiar with that
23. 93960 1:34 - 1:40
    class. So that you can form sub-classes, as we go, go along. Here's the
24. 99928 1:40 - 1:44
    question class. Have a look at it's methods, as you answer the next programming
25. 103732 1:44 - 1:48
    question. And here is a demo program, in which I want you to fill in some
26. 108454 1:48 - 1:55
    details. Make a question object, and then there is a method present question.
27. 114550 1:55 - 2:00
    That displays a question, gets the user response, checks whether was correct.
28. 119940 2:00 - 2:05
    They're methods for displaying and for checking a response. And I want you to
29. 124648 2:05 - 2:08
    look them up and call them.