[slf4j-dev] slf4j i8ln

[Ceki Gulcu]

Ralph Goers wrote:
>> * The provision of the Locale should be an orthogonal concept to the 
>> logging of messages and the creation of the Logger. This should be 
>> handled via the MDC.
> "could be handled via the MDC".  There are other ways to do it but that 
> is probably the simplest.

Pushing the locale in every thread will not suite everyone.

>> IMO there are still a few questions to answer:
>>
>> * Takeshi original design allowed you to use Enums as keys for 
>> messages. I'm personally not sure about this, I'm not really sure what 
>> benefits it offers over Strings as keys
> Enums are usually associated with an integer "value" and a String 
> description. The only value is that you might be able to get some 
> optimization by using the integer value of the enum in some cases. I 
> don't know that it is worth the effort to support it.

Unless enums have some other advantage that we did not think of. Takeshi can you 
describe the advantages of enums that you see?

>> * How does a framework provide translated messages [1] to i8ln layer? 
>> Can we also use the MDC here to push them in, and have the appender 
>> read them?
> I'm not sure I understand the question. The framework will provide a 
> method like:
> public String getMessage(String key, Object[] params);
> However the messages are stored is hidden behind the implementation of 
> that interface. Something has to call getMessage(). Potential places are 
> a) the application before calling SLF4J b) SLF4J before calling a 
> logging implementation, c) In the logging implementation - such as in 
> the Appender.

Bingo. a), b) or c) is the question. There is also a) and b) combined. See my 
previous message.

> Again, that depends. For example, Lillith 
> (http://freshmeat.net/projects/lilith-viewer) is an event viewer for 
> Logback. It would be very appropriate for it to do this. Likewise with 
> Apache Chainsaw for Log4j. Doing the L10N further up the chain limits 
> the flexibility these tools can provide. Sometimes that is desirable, 
> but my recommendation is to always start from as far back as possible 
> and move up the stack only as far as you have to.

If SLF4J or logback provided a reasonable solution, it would help developers in 
solving the logging i18n issue by the mere fact of offering and thus blessing a 
solution. It could only do harm if the offered solution was particularly stupid 
or bad. Moreover, the solution provided in slf4j or logback (or in both in part) 
could lay the foundation of a better solution imagined by one of our users.

> Ralph

-- 
Ceki Gülcü
Logback: The reliable, generic, fast and flexible logging framework for Java.
http://logback.qos.ch