On Tue, 29 Aug 2023 20:00:49 GMT, Nikita Sakharin <d...@openjdk.org> wrote:
>> `Collections.rotate` method contains a bug. This method throws
>> IndexOutOfBoundsException on arrays larger than $2^{30}$ elements. The way
>> to reproduce:
>>
>> final int size = (1 << 30) + 1;
>> final List<Byte> list = new ArrayList<>(size);
>> for (int i = 0; i < size; ++i)
>> list.add((byte) 0);
>> Collections.rotate(list, size - 1);
>>
>> Output:
>> ```Exception in thread "main" java.lang.IndexOutOfBoundsException: Index
>> -2147483648 out of bounds for length 1073741825```
>>
>> In that case private method `Collections.rotate1` will be called. And the
>> line:
>> `i += distance;`
>> will cause overflow. I fixed this method and wrote a test for it.
>>
>> I've signed the Oracle Contributor Agreement, but I don't have permission to
>> raise a bug in the JDK Bug System.
>>
>> Kindly ask you to raise a bug.
>
> Nikita Sakharin has updated the pull request incrementally with one
> additional commit since the last revision:
>
> 8314236: add comment for test
OK, looks reasonable.
-------------
Marked as reviewed by shade (Reviewer).
PR Review: https://git.openjdk.org/jdk/pull/15270#pullrequestreview-1627275045
