JShell: source in langtools vs JDK?

[Maurizio Cimadamore]

While I agree with many points you raise - I feel this discussion is 
very abstract; please try to run all langtools tests in the kulla 
langtools repo using your standard scripts - does everything still work 
for you? I found that I could not run tests using my usual scripts. The 
only way to run jshell tests reliably is through make. Now, if we were 
in a world where 100% langtools developers ran tests that way - I would 
agree with you; but the reality is somewhat different, and many 
developers are used to run langtools tests using some JDK N snapshot and 
bootstrapping the required classes. That technique WILL cease to work 
here. I don't think we can say to those developer - just don't run kulla 
tests and be happy (what if some of their changes accidentally broke 
something in kulla?). Are you saying that those developers should just 
stop doing what they are doing and start running langtools tests as part 
of a full JDK build and test cycle? That's a fine answer - I guess I'm 
just trying to guess where you are coming from.

Maurizio

On 17/09/15 01:04, Jonathan Gibbons wrote:
> I didn't say I think JShell should be in langtools, and I thought I 
> was being careful to be very explicit about that. I was just trying to 
> make sure we were making the right choice for the right reasons.
>
> The fact that it depends on JDI and jline is IMO a red herring. If 
> they were both already in JDK 8 (i.e. the boot JDK) would we be having 
> this discussion?
>
> To me, the bottom line is that I don't think it matters where the code 
> lives, and as a result I personally don't care and have no opinion 
> where the code should live. I /do/ think that whereever we choose to 
> put it, we can make everything work well from a developer standpoint, 
> without inconveniencing any existing developer usage, although I 
> concede that we might choose not to integrate it with the langtools 
> make/build.xml infrastructure and/or the existing NetBeans project.  
> And from a somewhat selfish standpoint, I think we have somewhat more 
> latitude to set things up the way we like it in the langtools repo 
> than we would in the jdk repo.
>
> I agree that JShell is higher up in the layers of abstraction than 
> javac, but I also don't think that the langtools repo is defined to be 
> "core tools to be able to work with the JDK". The provenance of the 
> repo (as indicated by its name) is that it was code that was managed 
> by the old Sun Language Tools Group, from way back when, meaning that 
> it was more of a "team" repository than a repository defined by a 
> layer of abstraction.
>
> So, for me, I think this comes down to, "where does the Kulla dev team 
> think it would be most convenient for them to keep and work on the 
> code?". Once we can answer that, we can move on to, "what is the most 
> convenient way to satisfy all the requirements of all the interested 
> parties?"
>
> -- Jon
>
>
> On 09/16/2015 04:02 PM, Maurizio Cimadamore wrote:
>> Jon, let's reverse the question - why do you think it *should* live 
>> in langtools? Honestly it feels very different from all other tools 
>> that live there; there's dependencies on JDI, jline - so to me it 
>> feels closer to other tools (i.e. jconsole) which already are in the 
>> jdk repo. I guess my argument is - if langtools defines the core 
>> tools to be able to work with the JDK, jshell feels like one ore two 
>> layer of abstractions on top of that.
>>
>> Maurizio
>>
>> On 16/09/15 23:31, Jonathan Gibbons wrote:
>>>
>>>
>>> On 09/16/2015 03:06 PM, Robert Field wrote:
>>>> As part of the JShell code review, Maurizio made the case that 
>>>> JShell should be in the JDK repo rather than langtools repo (where 
>>>> it is in the Kulla workspace).  We would like additional feedback 
>>>> on this before proceeding --
>>>>
>>>>> On Sep 11, 2015, at 8:25 AM, Maurizio Cimadamore 
>>>>> <maurizio.cimadamore at oracle.com> wrote:
>>>>>
>>>>> One general high-level comment, which I also pointed out 
>>>>> elsewhere, is that I'm not sure jshell really belongs in 
>>>>> langtools; while it's semantically (obviously) related to 
>>>>> langtools - it is a rather different beasts w.r.t. all other tools 
>>>>> in langtools-land; the fact that it depends on the JDK (for jline, 
>>>>> and for JDI in general) makes it very hard to run on top of a 
>>>>> random JDK and then bootstrapping classes - which is a technique 
>>>>> widely used to be able to run langtools tools w/o having to do a 
>>>>> full build cycle. More specifically, talking about IDE 
>>>>> integration, I don't see how IntelliJ/Netbeans langtools projects 
>>>>> (and the langtools internal developer ant build) could be updated 
>>>>> to be able to run/debug jshell w/o a full build.
>>>>
>>>>
>>>
>>> In the Big Picture view of the universe, folk would like to 
>>> restructure the repos in an OPenJDK forest, at which point the 
>>> distinction between the langtools and jdk repos will likely 
>>> disappear, or at least become very (very) blurred.  While that 
>>> change is not imminent, IMO opinion, it significantly reduces the 
>>> impact of the reasons why JShell should not be in langtools.
>>>
>>> I also don't entirely agree with the IDE reasons either.  If you 
>>> want to work on JShell in an IDE, you're going to have to do what it 
>>> takes to get rid of the red squiggly lines anyway, whatever repo the 
>>> code is in. To keep JShell out of Langtools because it doesn't fit 
>>> our current methodologies is a case of the tail wagging the dog.
>>>
>>> Also, I note that JDK 9 now builds the product module by module. In 
>>> times past, we built the world repo by repo, and that would indeed 
>>> have been good reason to keep JShell out of langtools, because of 
>>> the dependencies of JShell on JDK 9 API, like jline. But now, the 
>>> build will build "interim javac", and can then build JDK modules 
>>> like java.base and whatever module jline ends up in, and can then 
>>> build the module containing JShell.
>>>
>>> As to how to organize IDE projects, in the worst case, we keep the 
>>> langtools IDE setup as it is now (no JShell) and have a separate 
>>> project for JShell itself. That is tantamount to what we would do if 
>>> we push JShell into the jdk repo.
>>>
>>> So, I'm saying all that while trying to be agnostic on which repo it 
>>> should live in.    I don't really agree with the stated reasons why 
>>> it should not live in langtools, which means that we can look for 
>>> other reasons to choose one repo or another.
>>>
>>> -- Jon
>>
>