hg: penrose/penrose: 1. Update Penrose demos to support JSON format module info.

[Shi Jun Zhang]

On 7/5/2012 4:38 PM, David Bosschaert wrote:
> On 5 July 2012 06:50, Shi Jun Zhang<zhangshj at linux.vnet.ibm.com>  wrote:
>> On 7/4/2012 10:04 PM, David Bosschaert wrote:
>>> On 4 July 2012 12:04, David Bosschaert<david.bosschaert at gmail.com>   wrote:
>>>> On 4 July 2012 07:36, Shi Jun Zhang<zhangshj at linux.vnet.ibm.com>   wrote:
>>>>> 1. We need to add some document on how to write JSON format module info.
>>>>> I
>>>>> have to look into source code to learn how module-info.json structures
>>>>> and
>>>>> how to add modifiers.
>>>> Yes, this is correct. It would be great if we had a wiki to host this
>>>> information. But in the absence of that I'll create a document and
>>>> will share it some other way.
>>>> Currently there are 2 system tests that can be used as example:
>>>> *
>>>> http://hg.openjdk.java.net/penrose/jigsaw/jdk/file/507fae0a1d80/test/org/openjdk/jigsaw/hello-json.sh
>>>> *
>>>> http://hg.openjdk.java.net/penrose/jigsaw/jdk/file/1d2576346081/test/org/openjdk/jigsaw/hello-json-custom.sh
>>> I have checked some documentation in to the penrose code base in the
>>> absence of a wiki. You can find it here:
>>>
>>> http://hg.openjdk.java.net/penrose/penrose/raw-file/9b7beb1f525b/doc/PenroseModuleInfoJSON.html
>>>
>>> Hope this helps, let me know if you're missing anything.
>>>
>>> Cheers,
>>>
>>> David
>>>
>> That's great. As exports and permits are just set of strings in ModuleInfo
>> java object, can we simplify the representation in module-info.json?
>> Such as: "exports" : [ "x.y.z" ], "permits" : [ "x", "y" ]
> I actually made exports and permits JSON objects on purpose, because
> that way the value becomes extensible.
>
> In the case of exports, OSGi needs to be able to add version
> information (and possibly other attributes) to the export information.
> See the 'extensibility' section of [1] for an example.
>
> WRT to permits it's more a guess. I have a hunch that 'permits' may
> get more attributes in the future, that's why I turned it into an
> object.
>
> I think as a general rule its probably good to use JSON objects for
> anything that not purely a value. I.e. if the key is 'name' or
> 'version' then you're pretty sure you have a value but in other cases
> I using an object makes it possible to extend in the future without
> breaking bw compatibility. By that rule it would probably be better to
> rename the "class" entry into "main-class-name" as we're really
> talking about just a class name here.
>
> Cheers,
>
> David
>
> [1] http://hg.openjdk.java.net/penrose/penrose/raw-file/9b7beb1f525b/doc/PenroseModuleInfoJSON.html
>

Get it. Just think the JSON format is a little tedious.

-- 
Regards,

Shi Jun Zhang