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SLF4j logging exception with template params and stacktrace

I learn a new thing today.

I knew  that slf4j had two logger methods

org.slf4j.Logger.error(String, Object[])
org.slf4j.Logger.error(String, Throwable)

now If i wanted to call

        logger.error("This is {} message {}", "test" ,"to kp" ,e);


then I was under the impression that it would not print the stack trace as it would use the signature with object array.


But I was wrong :). It seems log4j has a nice trick and it would print the trace if the last argument is an exception object, a fellow programmer told me this that slf4j already handles this http://www.slf4j.org/faq.html#paramException .




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