Code review request for 6992121: StringBuilder.ensureCapacity(int minCap) throws OutOfMemoryError

[David Holmes]

Hi Mandy,

Given you can't actually test ArrayList I would drop it altogether and 
move the test to java/util/vector/TestEnsureCapacity

David

Mandy Chung said the following on 10/19/10 14:07:
>  On 10/18/10 4:54 PM, David Holmes wrote:
>> Hi Mandy,
>>
>> The functional changes seem ok. However the ArrayList test is not 
>> right because it checks the size not the capacity. The same with the 
>> Vector test, though at least with Vector you can check capacity().
>>
> 
> I missed the Vector.capacity() method.  Thanks.   I updated the test.
>    http://cr.openjdk.java.net/~mchung/6992121/webrev.01/
>> I find it odd that ArrayList has a very well defined notion of 
>> capacity yet no method to query that capacity.
>>
> 
> True.  I don't have the history but wonder if this is intentional.
> 
> Mandy
> 
>> David
>>
>> Mandy Chung said the following on 10/19/10 08:41:
>>>  Please review the fix for:
>>>
>>> 6992121: StringBuilder.ensureCapacity(int minCap) throws 
>>> OutOfMemoryError with minCap=Integer.MIN_VALUE
>>>
>>> Webrev at:
>>>     http://cr.openjdk.java.net/~mchung/6992121/webrev.00/
>>>
>>> This is a regression caused by the changes for 6933217 (Huge arrays 
>>> handled poorly in core libraries).   The ensureCapacity() method in 
>>> the StringBuffer, StringBuilder, ArrayList, and Vector classes are a 
>>> public API that accepts negative numbers.   The following 
>>> overflow-conscious code:
>>>
>>>   if (minimumCapacity - value.length>  0)
>>>
>>> considers negative minimumCapacity as overflow case where 
>>> OutOfMemoryError will be thrown.  So the implementation of the public 
>>> ensureCapacity() methods need to check if the input argument is 
>>> positive before doing the above overflow-conscious check.
>>>
>>> Thanks
>>> Mandy
>