[hibernate-dev] OGM: CheckStyle and imports due to JavaDoc comments

[Emmanuel Bernard]

On 31 juil. 2013, at 13:14, Hardy Ferentschik wrote:

> 
> On 31 Jan 2013, at 10:41 AM, Gunnar Morling <gunnar at hibernate.org> wrote:
> 
>> Personally I prefer to include a class via fully qualified name if it is only used in the javadocs.
>> I think the readability does not suffer too much and adding an actual import has actually
>> runtime consequences. We already had cases where a javadoc import caused a hard link
>> between code which is otherwise decoupled.
>> 
>> WDYM exactly by "hard link" in this context? Is it about referencing a type from an optional dependency which might not be present at runtime?
> 
> Right, optional dependencies. Take JPA and Search. In the engine module we avoid importing it directly and do processing of
> @Id reflectively. Having an import of javax.persitence.Id would create a runtime dependency.
> 
>> I just tried out this scenario (adding an import statement just for JavaDoc to a type which is not present at runtime) and still could execute the importing class
>> without problems. Only when accessing the imported type in the actual code I'm getting a CNFE. But this might be specific to the VM in use, not sure.
> 
> We had this discussion now several times. I remember when we wrote this reflection code the first time (many years back ;-))
> all referenced classes were eagerly loaded. In this case just having the import statement required the class being 
> available at runtime.  Obviously this must have changed a bit which also is proven by your experiment. 
> 

Of course my memory might be flawed but the problems I recall around isolating a piece of code for hv, search and later bean validation from core did not involve unused imports. Come to think of it, I have never seen an *unused* import eagerly loading a class even though in practice it's left unspecified by the JLS.