RFR: 8246778: Compiler implementation for Sealed Classes (Second Preview)

[David Holmes]

Hi Harold,

On 24/11/2020 6:27 am, Harold Seigel wrote:
> Hi David,
> 
> Thanks for looking at this.
> 
> The intent was for method Class.permittedSubclasses() to be implemented 
> similarly to Class.getNestMembers().  Are you suggesting that a security 
> manager check be added to permittedSubclasses() similar to the security 
> manager check in getNestMembers()?

No I'm suggesting the change to the API is plain wrong. :) Please see 
discussion in the CSR.

Cheers,
David

> Thanks, Harold
> 
> On 11/18/2020 12:31 AM, David Holmes wrote:
>> Hi Vincente,
>>
>> On 16/11/2020 11:36 pm, Vicente Romero wrote:
>>> Please review the code for the second iteration of sealed classes. In 
>>> this iteration we are:
>>>
>>> - Enhancing narrowing reference conversion to allow for stricter 
>>> checking of cast conversions with respect to sealed type hierarchies.
>>> - Also local classes are not considered when determining implicitly 
>>> declared permitted direct subclasses of a sealed class or sealed 
>>> interface
>>
>> The major change here seems to be that getPermittedSubclasses() now 
>> returns actual Class objects instead of ClassDesc. My recollection 
>> from earlier discussions here was that the use of ClassDesc was very 
>> deliberate as the permitted subclasses may not actually exist and 
>> there may be security concerns with returning them!
>>
>> Cheers,
>> David
>> -----
>>
>>> -------------
>>>
>>> Commit messages:
>>>   - 8246778: Compiler implementation for Sealed Classes (Second Preview)
>>>
>>> Changes: https://git.openjdk.java.net/jdk/pull/1227/files
>>>   Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1227&range=00
>>>    Issue: https://bugs.openjdk.java.net/browse/JDK-8246778
>>>    Stats: 589 lines in 12 files changed: 508 ins; 18 del; 63 mod
>>>    Patch: https://git.openjdk.java.net/jdk/pull/1227.diff
>>>    Fetch: git fetch https://git.openjdk.java.net/jdk 
>>> pull/1227/head:pull/1227
>>>
>>> PR: https://git.openjdk.java.net/jdk/pull/1227
>>>