[9] Review request: 8178015: Clarify requirement for app modules to export/open packages to javafx modules

[Mandy Chung]

+1
Mandy

> On Apr 20, 2017, at 11:06 AM, Kevin Rushforth <kevin.rushforth at oracle.com> wrote:
> 
> Here is an updated webrev with a few suggested wording changes (e.g., removed the reference to ModuleDescriptor, changed "accessible by" back to "accessible to").
> 
> http://cr.openjdk.java.net/~kcr/8178015/webrev.02/
> 
> Additionally, I removed the example in the FXML annotation showing the use of "opens to" in module-info.java (but left the example in Application).
> 
> -- Kevin
> 
> 
> Kevin Rushforth wrote:
>> 
>> 
>> Mandy Chung wrote:
>>>> On Apr 18, 2017, at 12:48 PM, Kevin Rushforth <kevin.rushforth at oracle.com> wrote:
>>>> 
>>>> 
>>>> 
>>>> Alan Bateman wrote:
>>>>   
>>>>> On 18/04/2017 19:19, Kevin Rushforth wrote:
>>>>>     
>>>>>> Good suggestion. Here is an updated webrev with Mandy's suggestion and yours:
>>>>>> 
>>>>>> http://cr.openjdk.java.net/~kcr/8178015/webrev.01/
>>>>>> 
>>>>>> -- Kevin
>>>>>>        
>>>>> This looks mostly okay.
>>>>> 
>>>>> I guess for FXML then I assume that the annotated member could be public, in which case the package just needs to be exported (no need to open).
>>>>>      
>>>> Yes, it could be, but the more typical use of the annotation is on non-public members, so that was why I chose that as the example.
>>>>    
>>> 
>>> I have the same comment as Alan.  The example in the javadoc may be perceived as a recommendation.  We should probably recommend the annotated member be moved to public and encapsulated in its module, just exports it to javafx.fxml to use.    
>> 
>> For the use of the FXML annotation, that is exactly the recommendation. If you want the FXMLLoader to modify a public member in a public class, you don't need the annotation at all (although I guess it can still be used as useful documentation).
>> 
>> In the longer "Introduction to FXML" doc, which is included with the API docs and linked from the javafx.fxml package description, the only examples we give of using the @FXML annotation are for non-public members. See:
>> 
>> http://download.java.net/java/jdk9/jfxdocs/javafx/fxml/doc-files/introduction_to_fxml.html#fxml_annotation 
>> 
>> Specifically, the description of the FXML annotation says:
>> 
>>   However, for developers who prefer more restricted visibility for
>>   controller fields or handler methods, the javafx.fxml.FXML
>>   annotation can be used. This annotation marks a protected or private
>>   class member as accessible to FXML.
>> 
>> 
>> For consistency, it seems best to show the example in the FXML javadocs as an example of using "opens" since that is what would be needed for the typical use case, such as those we document elsewhere.
>> 
>> -- Kevin
>> 
>> 
>>> Mandy