Re: [jakartaee-tck-dev] Unable to run Servlet TCK on Java 11

[Mark Thomas <markt@xxxxxxxxxx>]

On 20/06/2020 03:31, Scott Marlow wrote:
> 
> 
> On 6/19/20 9:07 AM, Mark Thomas wrote:
>> Hi,
>>
>> I am currently working the Servlet TCK and have hit an issue when
>> running on Java 11.
>>
>> The Servlet TCK tests HTTP/2 functionality. To do this is uses an HTTP/2
>> client provided by http.jar. This appears the Java 9 module
>> jdk.incubator.http ported to Java 8. I can't find the source code for
>> ported version anywhere. The issue is that the ported code references
>> sun.misc.InnocuousThread which isn't present in Java 11.
>>
>> I have looked at several potential solutions:
>>
>> 1. Avoid the code that triggers loading of InnocuousThread
>> This isn't possible.
>>
>> 2. Switch to a different HTTP/2 client. Apache HttpClient 5.0 supports
>> HTTP/2 but that would require an upgrade to HttpClient 5.0 for at least
>> all of the Servlet 5.0 TCK. It should be a safe upgrade but there are
>> risks attached to an upgrade. I dismissed this option due to the risks.
> 
> Perhaps for EE10, although I don't think we have much TCK code that
> directly uses the jdk.incubator.http code (just
> src/com/sun/ts/tests/servlet/spec/serverpush/Client.java).  Did I miss a
> reference?

I don't think so. I'm more concerned about the other TCK code that is
already using the Apache Http Client and the impact of any upgrade.
Olivier's message has a better summary of the position here.

>> 3. Provide a Java 11 version of these TCK tests that uses the
>> java.net.http API. This should be fairly easy to write but it would then
>> require the Servlet TCK to be compiled with Java 11. I am assuming that
>> a change to compiling with Java 11 is not an option at this stage.
> 
> As others said, this could work.
> 
>>
>> 4. Use reflection to provide a Java 8 compilable solution that uses Java
>> 11 features when running on Java 11. This looks possible but is a lot of
>> work. It appears to be made more complex by changes in the API between
>> the incubator stage in Java 9 and the final version in Java 11.
> 
> This could also work.
> 
>>
>> 5. Use BCEL to remove the references to InnocuousThread in http.jar.
>> This looks doable at this stage. There may be further complications once
>> the InnocuousThread issues are fixed.
>>
>> My current thinking is:
>> - explore option 5
>> - if it works, provide the code I use to 'patch' http.jar in a text file
>>    along side the HTTP/2 tests along with the patched JAR in a PR
> 
> If we could find the jdk.incubator.http source, would it make sense to
> request transferring the source to Eclipse so that it could be
> maintained via source level changes?  Not much time left for that, but
> if that is what we want for the future, we should get that started.  Or
> is it more likely that we would just switch to Apache HttpClient 5.0 for
> EE 10?

I think that is a fair amount of work for code we won't be using for
very long. My BCEL hack worked and is fully documented (see the PR) so I
think this is OK for a short-term (Jakarta EE 9 only) fix.

I think a longer term fix is a rationalisation of the HTTP clients. I'll
reply with my thoughts to Olivier's mail.

Mark