SLF4J_MANUALLY_PROVIDED_MESSAGE should be ignored for TRACE and DEBUG

[melloware]

In certain scenarios we want to log a DEBUG of just the localized message and not the full stack trace...

  } catch (BusinessException e) {
     final String localizedMessage = e.getLocalizedMessage();
     LOG.debug("Reporting BusinessException for method {}: {}", new Object[] { methodName, localizedMessage });

We are getting the SLF4J_MANUALLY_PROVIDED_MESSAGE error. Maybe that should only be for INFO and higher or WARN and higher?

[KengoTODA]

Hi @melloware, thanks for your contribution and sorry for my delay.

Could you explain why you don't log stacktrace of e? To keep your log short? It might help me to understand your request.

I will consider how to support this case, but I think, switching by log level isn't cool because logging policy (when/how to use each level) depends on project. Currently I think it is better to switch by existence of e like below.

// invalid: duplicated message will be logged.
LOG.debug("Reporting BusinessException for method {}: {}", new Object[] { methodName, localizedMessage, e });
// valid: message will be logged only once.
LOG.debug("Reporting BusinessException for method {}: {}", new Object[] { methodName, localizedMessage });

[melloware]

My thought was this was an Exception that the user is going to have displayed as some sort of ValidationException or BusinessException. I want to log a single line in the log file just to let the log know this error is going back to the user but since its not a "true" exception I don't want the whole stack trace. Because then the logs get filled with stacktraces for basically validation errors.

That was my only thought.

[KengoTODA]

OK, I got it. Then it is better to switch by existence of e.
Thanks for your feedback, I'll try to implement it.

[KengoTODA]

@melloware
Today I have released version 1.2.0 and it will be deployed onto Maven central soon.
Could you try this version? It should be solution for your case.

• https://github.com/KengoTODA/findbugs-slf4j/releases/tag/findbugs-slf4j-1.2.0

Note that I tested 1.2.0 on Java 8. If your product depends on Java 7 or older one, it might have problem.