RFR: JDK-8226585: Improve javac messages for using a preview API

[Magnus Ihse Bursie]

On 2019-10-16 14:55, Erik Joelsson wrote:
> Build change looks good now.
I agree.

/Magnus
>
> /Erik
>
> On 2019-10-16 05:50, Jan Lahoda wrote:
>> Hi,
>>
>> An updated patch is here:
>> http://cr.openjdk.java.net/~jlahoda/8226585/webrev.02/
>>
>> Changes in the update:
>> -added the dependency into the makefiles
>> -loosened the handling of essential preview APIs when 
>> --enable-preview and @SuppressWarnings is applied - there is no 
>> warning for the essential APIs (as there is no warning in such a case 
>> for non-essential APIs). This is per the discussion in the CSR:
>> https://bugs.openjdk.java.net/browse/JDK-8231411
>>
>> Any comments/feedback on this?
>>
>> Thanks!
>>     Jan
>>
>> On 09. 10. 19 17:41, Erik Joelsson wrote:
>>> Oh, you are absolutely correct, the dependency is missing.
>>>
>>> We need something like this inside "define SetupInterimModule":
>>>
>>> $$(BUILD_$1.interim): $(COPY_PREVIEW_FEATURES)
>>>
>>> /Erik
>>>
>>> On 2019-10-09 01:42, Magnus Ihse Bursie wrote:
>>>> I can’t see how the compilation is dependent on the copy being 
>>>> finished. Since Erik contributed this it will probably be correct 
>>>> :) but I’d appreciate an explanation on how this dependency is 
>>>> guaranteed.
>>>>
>>>> Or maybe I’m misunderstanding what this is supposed to do?
>>>>
>>>> /Magnus
>>>>
>>>>> 8 okt. 2019 kl. 17:27 skrev Jan Lahoda <jan.lahoda at oracle.com>:
>>>>>
>>>>> Thanks for the new code Erik!
>>>>>
>>>>> A new webrev/patch that includes this better way of copying is here:
>>>>> http://cr.openjdk.java.net/~jlahoda/8226585/webrev.01/
>>>>>
>>>>> Any feedback is welcome!
>>>>>
>>>>> Thanks,
>>>>>     Jan
>>>>>
>>>>>> On 03. 10. 19 18:06, Erik Joelsson wrote:
>>>>>> Hello Jan,
>>>>>> The build change looks ok, but I would recommend this construct 
>>>>>> for copying the file instead:
>>>>>> $(eval $(call SetupCopyFiles, COPY_PREVIEW_FEATURES, \
>>>>>>      FILES := 
>>>>>> $(TOPDIR)/src/java.base/share/classes/jdk/internal/PreviewFeature.java, 
>>>>>> \
>>>>>>      DEST := 
>>>>>> $(BUILDTOOLS_OUTPUTDIR)/gensrc/java.base.interim/jdk/internal/PreviewFeature.java, 
>>>>>> \
>>>>>> ))
>>>>>> TARGETS += $(COPY_PREVIEW_FEATURES)
>>>>>> Then you automatically get all the corner case handling we have 
>>>>>> implemented over the years for logging, making directories and 
>>>>>> copying files. Your version is still correct for this case though.
>>>>>> /Erik
>>>>>>> On 2019-10-03 02:57, Jan Lahoda wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> This is a continuation of Joe's patch from here:
>>>>>>> https://mail.openjdk.java.net/pipermail/compiler-dev/2019-June/013498.html 
>>>>>>>
>>>>>>>
>>>>>>> APIs associated with preview features are split into two groups: 
>>>>>>> essential and non-essential. These are marked with an 
>>>>>>> JDK-internal annotation, PreviewFeature, and a tag in the 
>>>>>>> javadoc, @preview. The javac follows the PreviewFeature 
>>>>>>> annotation, and produces either warnings or errors for the 
>>>>>>> usages of such APIs. For the @preview tag, there is a taglet in 
>>>>>>> the JDK build that adds the content of the tag into the 
>>>>>>> documentation. The first part of the @preview's text goes into 
>>>>>>> the summary, the second part goes into the detailed description.
>>>>>>>
>>>>>>> For build, a tricky problem is that the jdk.compiler module uses 
>>>>>>> the PreviewFeature annotation as well, but that is not in the 
>>>>>>> bootstrap JDK. So, for the intermediate langtools build, the 
>>>>>>> PreviewFeature annotation is copied from java.base.
>>>>>>>
>>>>>>> Proposed webrev:
>>>>>>> http://cr.openjdk.java.net/~jlahoda/8226585/webrev.00/
>>>>>>>
>>>>>>> Javadoc with the change:
>>>>>>> http://cr.openjdk.java.net/~jlahoda/8226585/docs.00/api/index.html
>>>>>>>
>>>>>>> See for example:
>>>>>>> http://cr.openjdk.java.net/~jlahoda/8226585/docs.00/api/java.base/java/lang/String.html 
>>>>>>>
>>>>>>> http://cr.openjdk.java.net/~jlahoda/8226585/docs.00/api/jdk.compiler/com/sun/source/tree/CaseTree.html 
>>>>>>>
>>>>>>>
>>>>>>> JBS:
>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8226585
>>>>>>>
>>>>>>> CSR:
>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8231411
>>>>>>>
>>>>>>> Feedback is welcome!
>>>>>>>
>>>>>>> Thanks,
>>>>>>>      Jan