[15] RFR: 8239836: ZoneRules.of() doesn't check transitionList/standardOffsetTL arguments validity

[Roger Riggs]

Hi Naoto,

look ok.

ZoneRules.java: 488, 644, 761, 791
I'd suggest calling isFixedOffset() instead of repeating the code:
standardTransitions.length == 0 && savingsInstantTransitions.length == 0

It should be inlined in cases where the performance matters.

Thanks, Roger


On 2/27/20 3:41 PM, naoto.sato at oracle.com wrote:
> Hello,
>
> Please review the fix to the following issue:
>
> https://bugs.openjdk.java.net/browse/JDK-8239836
>
> The proposed changeset is located at:
>
> https://cr.openjdk.java.net/~naoto/8239836/webrev.00/
>
> It turned out that 'transitionList' is not necessarily a superset of
> 'standardOffsetTransitionList', as in some occasions where a standard 
> offset change and a savings change happen at the same time (canceling 
> each other), resulting in no wall time transition. This means that the 
> "rules" in the sample code is a valid ZoneRules instance.
>
> However, there is an assumption in ZoneRules where no (wall time) 
> transition means the fixed offset zone. With that assumption, the 
> example rule is considered a fixed offset zone which is not correct. 
> So the fix proposed here is not to throw an IAE but to recognize the 
> rule as a valid, non-fixed offset ZoneRules instance.
>
> Naoto
>
>