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SCJP Java 6: Selftest K&B Chapter 3 Question 7 point private

 
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Hello Colleagues,

I have a question about Java 6: Selftest K&B Chapter 3 Question 7. Why does the code work while
points in line 8 is private, but nop error occurs in line 13 where points is used?

3. public class Bridge {
4. public enum Suits {
5. CLUBS(20), DIAMONDS(20), HEARTS(30), SPADES(30),
6. NOTRUMP(40) { public int getValue(int bid) {
return ((bid-1)*30)+40; } };
7. Suits(int points) { this.points = points; }
8. private int points;
9. public int getValue(int bid) { return points * bid; }
10. }
11. public static void main(String[] args) {
12. System.out.println(Suits.NOTRUMP.getValue(3));
13. System.out.println(Suits.SPADES + " " + Suits.SPADES.points);
14. System.out.println(Suits.values());
15. }
16. }

Thanks for helpingin advance!
Martin
 
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Look at the line 13 carefully, how 'points' varibale is being access and can you told us what is the visibility of private variable ?
And please use CodeTags and welcome to JR
 
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This question was answered here.
 
Greenhorn
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That's a good point, how could I miss that!!! The link has a good answer by the way.
My attention was drawn to somwhere else, in the answer. A and B are correct:

A. The output could contain 30
B. The output could contain @bf73fa

The first is pretty obvious, what I can't figure out is how to calculate the second. I am guessing that it might be the String representation of Suits.values() array object. But I still don't know how I can come up with this answer without actually running the code on the machine.
 
Martijn Wassenberg
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Thanks very much for the support.
The link solved everything! I was not that in the book where the innerclass was described.

Martijn
 
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