On 31 août 2011, at 10:52, Felix Knecht wrote:
> Hi Pierre-Arnaud,
>
> On 08/31/2011 10:33 AM, Pierre-Arnaud Marcelot wrote:
>> Hi Felix,
>>
>> On 31 août 2011, at 10:07, Felix Knecht wrote:
>>
>>> On 08/31/2011 09:08 AM, Pierre-Arnaud Marcelot wrote:
>>>> On 30 août 2011, at 15:32, Emmanuel Lecharny wrote:
>>>>
>>>>> Hi guys,
>>>>
>>>> Hi,
>>>>
>>>>> we just had a private convo with Pierre-Arnaud about coding rules. We are
>>>>> not following exactly the same type of rules in Studio and in ADS, which
>>>>> is quite normal. There are some reason why there is a divergence.
>>>>
>>>> As we've seen in our private convo with Emmanuel, the divergence is very
>>>> very subtle and it's mostly a divergence on "unwritten" rules that we
>>>> can't find in our coding standards documentation...
>>>> The rest of rules are clearly well followed (except some very very old
>>>> parts of code that haven't been touch for years now).
>>>>
>>>>> I think we need to discuss a few things here.
>>>>>
>>>>> Currently, we have a small coding standard page :
>>>>> https://cwiki.apache.org/confluence/display/DIRxDEV/Coding+standards
>>>>>
>>>>> It's pretty simple, with not a lot of rules. Both ADS and Studio are more
>>>>> or less following those rules which were established a long time ago
>>>>> (there are still some very old files in ADS which are not following those
>>>>> rules, but with more than 3000 files on the project, we won't spend one
>>>>> month reviewing all of those files one by one...)
>>>>
>>>> Same thing for Studio.
>>>> Some pretty old files may not be following *all* the rules.
>>>>
>>>>> I'd like to add a few more rules, at least for ADS, and suggest that
>>>>> Studio keep a slightly different sets of rules, but in any case, I'd like
>>>>> to see all the rules added to the wiki.
>>>>>
>>>>> Here is what I think would be good for ADS :
>>>>> - add a blank line before each 'if', 'for', 'do', 'switch', 'case' unless
>>>>> the previous line is a '{'
>>>>
>>>> In most cases I agree, but I find some cases where I prefer leaving the if
>>>> close to the previous expression.
>>>> Especially in cases where I get a variable and I want to test something on
>>>> it just after.
>>>> Here's an example:
>>>>>> // Testing variable
>>>>>> SomeType variable = anotherVariable.getVariable();
>>>>>> if ( variable.hasFlag() )
>>>>>> {
>>>>>> [...]
>>>>
>>>> In that particular case, IMO, it helps grouping expressions for a better
>>>> readability.
>>>>
>>>>> - get rid of trinary operator ( expr ? op1 : op2 )
>>>>
>>>> I would prefer keeping it as it's very handy for variable nullity checks.
>>>>
>>>> Here's an example:
>>>>>> return ( ( variable == null ) ? "null" : variable );
>>>>
>>>>
>>>> I prefer the compact format instead of this:
>>>>>> if ( variable == null )
>>>>>> {
>>>>>> return "null";
>>>>>> }
>>>>>> else
>>>>>> {
>>>>>> return variable;
>>>>>> }
>>>>
>>>> Now, if I'm the only one liking it, I will refrain myself from using it in
>>>> the future... ;)
>>>>
>>>>> - add a blank line before each 'return'
>>>>
>>>> +1
>>>>
>>>>> - in if ( expr ), we should use '(' and ')' for expressions containing an
>>>>> '==' or any other logical connector
>>>>
>>>> +1
>>>>
>>>>> We also may want to add some rules for pom.xml.
>>>>
>>>> +1
>>>> Even though I think we already share the same rules, having them written
>>>> is always a plus. Especially for newcomers.
>>>>
>>>>> Typically, what I'd like to see is a blank line between each element
>>>>> like<dependency>. Here is an example :
>>>>>
>>>>> <dependencies>
>>>>> <!-- Apache Directory Studio library plugins dependencies -->
>>>>> <dependency>
>>>>> <groupId>org.apache.directory.shared</groupId>
>>>>> <artifactId>shared-ldap-model</artifactId>
>>>>> <scope>provided</scope>
>>>>> </dependency>
>>>>>
>>>>> <dependency>
>>>>> <groupId>org.apache.directory.shared</groupId>
>>>>> <artifactId>shared-util</artifactId>
>>>>> <scope>provided</scope>
>>>>> </dependency>
>>>>>
>>>>> This is to separate all the items which have the same dame, for clarity
>>>>> sake.
>>>>
>>>> Why not.
>>>> I liked the idea of grouping a set of dependencies under a common "label"
>>>> like this "Apache Directory Studio library plugins dependencies" in your
>>>> example.
>>>> But adding a blank line doesn't really break either...
>>>> So, +1.
>>>>
>>>> One more thing I'd like to add to pom.xml guidelines, I really like when
>>>> dependencies are ordered in alphabetical order.
>>>> In Studio, we deal with a lot of dependencies for each project (mostly
>>>> Eclipse dependencies + a few others) and having them ordered REALLY helps
>>>> when looking for something, IMO.
>>>
>>> I absolutely agree. On which tag (groupId | artifactId) would you order
>>> them? No matter wich one we take it should be the first tag
>>> after<dependency>, so for artifactId it would be
>>>
>>> <dependency>
>>> <artifactId>shared-ldap-model</artifactId>
>>> <groupId>org.apache.directory.shared</groupId>
>>> </dependency>
>>>
>>> Ordering by groupId would make it possible to group then under a common
>>> "label".
>>
>> My personal preference would be to keep the structure of a dependency
>> element the way it is used at the moment (groupId tag first then and
>> artifactId in second), like this:
>> <dependency>
>> <groupId>${groupId}</groupId>
>> <artifactId>${artifactId}</artifactId>
>> </dependency>
>>
>> I would order dependencies by groupId first and then, in the case of an
>> identical groupId, I would order them via their artifactId.
>>
>> That's why I think we should stick with the order groupId, artifactId.
>> But I might be wrong. ;)
>
> I don't think that you're wrong, I totally agree with this.
>
>>
>> Of course, ordering rules should not applied on "labels" themselves and
>> "labels" could be ordered the way we want, according to the importance of
>> each "label".
>> BUT, in each label, the dependencies should be ordered by alphabetical order.
>>
>> This scheme would allow to have different regroupments ("labels") ordered by
>> importance and each of the regroupments dependencies would be classified by
>> alphabetical order.
>>
>> Does it make sense?
>
> I'm not that positive of these regroupments ("labels").
> - Having an alphabetic ordering I'd assume to find a dependency according the
> ordering - this might not be the case because of the regroupments.
> - Where do overridden transitive dependencies belong? Into the regroupment of
> it's parent? Into a regroupment labeled "miscellaneous"?
> - What are the criterias about the importance of a label?
>
> That's why I'd have them ordered as you proposed (groupId/artifactId) but not
> regrouped by importance.
Actually, this concept of regroupments isn't something new and that's something
that is already in place in both ApacheDS and Studio pom.xml files.
In ApacheDS, we use to have ApacheDS' own modules dependencies first, then
Shared dependencies, then Commons dependencies, etc. etc...
But your questions above are perfectly valid...
I do believe that we really have a tendency to organize things into groups
(like files in folders) and that can be (and already is) the case for
dependencies in our pom files.
Some dependencies gets regrouped automatically because they share a common
groupId for example.
But we might like to regroup two or more dependencies that are far away in
terms of alphabetical order but that are related in terms of purpose.
An example to that would be our logging dependencies.
Here's an excerpt from ApacheDS' pom.xml (line 898-916):
>> <!-- Logging dependencies -->
>>
>> <dependency>
>> <groupId>org.slf4j</groupId>
>> <artifactId>slf4j-api</artifactId>
>> <version>${slf4j.api.version}</version>
>> </dependency>
>>
>> <dependency>
>> <groupId>org.slf4j</groupId>
>> <artifactId>slf4j-log4j12</artifactId>
>> <version>${slf4j.log4j12.version}</version>
>> </dependency>
>>
>> <dependency>
>> <groupId>log4j</groupId>
>> <artifactId>log4j</artifactId>
>> <version>${log4j.version}</version>
>> </dependency>
Some of these dependencies would have been far away from each other when
classified by alphabetical order but here, regrouped as common "Logging
dependencies" set, I think they make more sense.
Regards,
Pierre-Arnaud
> Regards
> Felix
>
>>
>>>>
>>>>> For Studio, I let Stefan and Pierre-Arnaud define the rules they prefer
>>>>> to use, as i'm not working often on its code.
>>>>
>>>> For the sake of a better interaction and simplicity, I think we should
>>>> share the same rules across the whole Directory project.
>>>> As I'm mostly the only dissident on some of the facts above, I can and
>>>> will adapt myself.
>>>> Not a big deal (except for the trinary operator... ;) ).
>>>>
>>>> Regards,
>>>> Pierre-Arnaud
>>>>
>>>>
>>>>> Any comments ?
>>>>>
>>>>> --
>>>>> Regards,
>>>>> Cordialement,
>>>>> Emmanuel Lécharny
>>>>> www.iktek.com
>>>>>
>>>>
>>>
>>
>
