[Fwd: Code review request: 7072353 JNDI libraries do not build with javac -Xlint:all -Werror]

[Joe Darcy]

David Holmes wrote:
> Joe Darcy said the following on 08/04/11 12:33:
>> David Holmes wrote:
>>>> Using wildcards makes the subtyping work along the type argument axis.
>>>
>>> So what is the right fix here? To declare the underlying Vector as a 
>>> Vector<?> and cast it to something concrete when needed? It seems 
>>> very wrong to me to be inserting raw type casts all through this code.
>>
>> It isn't entirely clear to be from a quick inspection of the code 
>> what the actual type usage is.  A writable general Vector should be a 
>> Vector<Object> and Vector just meant for reading should be a 
>> Vector<?> (or the equivalent Vector<? extends Object>).
>>
>> If the type usage is "a sequence of X's and Y's" where X and Y don't 
>> have some useful supertype, I would recommend using a somewhat 
>> different set of data structures, like a list of type-safe 
>> heterogeneous containers or a list of a new package-level XorY class.
>
> Buried in one of Sasha's emails it says:
>
> "The current code uses it to store Strings and Vector<String>s."
>
> Hence it is declared Vector<Object>.
>
> This is looking to me like code that should not have been generified.
>

Hmm.  If String or Vector<String> are the two kinds of stored values, I 
would recommend Vector<Vector<String>> where a lone string was wrapped 
in a vector.  (Actually, I would recommend a List<List<String>>, but 
that may be beyond the scope of this cleanup.

-Joe