Is lower bound in Java exclusive or inclusive?

Question

I am reading Java the Complete Reference 7th edition, and it says that lower bound in Java Generics are exclusive, but I found the opposite here (It says that it is inclusive.) Is it because SE 6 differs from SE 7?

Edit: Java the Complete Reference 7th edition discussed SE 6.

Where exactly does it say that generic bounds in java 7 are exclusive? — Bohemian, May 25 '13 at 04:35
@Bohemian You mean the book? It is mentioned in 'Using Wildcard Arguments' in Generics chapter. This edition discusses SE 6, not 7, so I thought there might be a difference. — Ghasan غسان, May 25 '13 at 04:41
Well the book is wrong! Generic bounds are *inclusive* no matter which version of java you are using. Just because some bozo writes something in a book does not make it so. — Bohemian, May 25 '13 at 05:27

score 2 · Answer 1 · edited May 25 '13 at 04:25

2

The bound is inclusive.

It is very easy to try it by yourself:

import java.util.*;
import java.lang.*;

class Main {
        public static void main (String[] args) throws java.lang.Exception {
                addNumbers(new ArrayList<Integer>());   
        }
        public static void addNumbers(List<? super Integer> list) {
                for (int i = 1; i <= 10; i++) {
                        list.add(i);
                }
        }
}

edited May 25 '13 at 04:25

Cameron Skinner

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answered May 25 '13 at 04:20

guido

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You haven't really answered the question. I don't have a compiler handy, so I can't tell if your code compiles. Is the bound inclusive or exclusive? – Cameron Skinner May 25 '13 at 04:24
1

@CameronSkinner It's inclusive. The link he provided will compile and run for you, online. – wchargin May 25 '13 at 04:24
I've edited the answer to include the short version. Thanks @WChargin for clarifying :) – Cameron Skinner May 25 '13 at 04:25

score 1 · Accepted Answer · answered May 25 '13 at 04:30

In the specification, they use the word "subtype" in parametrization to mean inclusive subtype. In section 4.10, it defines the phrase "proper subtype/proper supertype" to mean exclusive subtype/supertype while "subtype/supertype" means inclusive subtype/supertype.

Is lower bound in Java exclusive or inclusive?

2 Answers2