JDK 16 RFR of JDK-8250660: Clarify that WildcardType and AnnotatedWildcardType bounds methods return one

Mandy Chung mandy.chung at oracle.com
Wed Aug 5 21:41:52 UTC 2020

This looks good.  This will prepare for the future when Java supports 
multiple bounds.


On 8/5/20 2:37 PM, Joe Darcy wrote:
> Hello,
> Addressing some feedback from off-list discussions with Mandy, I 
> propose changing the API notes to:
>     @apiNote While to date a wildcard may have at most one 
> upper[lower] bound, callers of this method should be written to 
> accommodate multiple bounds.
> Thanks,
> -Joe
> On 8/3/2020 9:24 AM, Joe Darcy wrote:
>> Hi David,
>> To provide a bit more context, the API was consciously designed to be 
>> future-proofed against the possibility of Java supporting multiple 
>> bounds here (JDK-4891872). As of yet, that change has not come to 
>> pass, and as you note may never come to pass. So besides in addition 
>> to the links into the JLS, I think it is reasonable to include an API 
>> note acknowledging the situation. How about:
>>     This method supports the existence of multiple bounds, but to 
>> date, a wildcard may have at most one upper/lower bound.
>> -Joe

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