[slf4j-user] Trying to use log4j-over-slf4j

Raymond Cramer rnc at bodc.ac.uk
Thu Oct 30 17:26:54 CET 2008


Hi Ceki,

Thanks for the rapid response. They are defined as Maven dependencies, slf4j-api is 1.5.5 and log4j-over-slf4j is 1.5.4.

I have no idea what versions the netcdf package was expecting.

Hope thats clearer
Ray
>>> listid at qos.ch 30/10/2008 16:12 >>>
Hello Raymond,

Raymond Cramer wrote:

 > I'm new to slf4j, having been using log4j. I am trying to use a
 > package (netcdf) that requires slf4j, but am having problems getting
 > my head around some of this stuff.
 >
 > 1) If I have an application (which uses log4j) deployed through
 > Tomcat, do I simply replace the log4j jar file with log4j-over-slf4j
 > and slf4j-api jar files? Because when I do this the application
 > doesn't run at all- I get the HTTP Status 404 error that my JSP can't
 > be found.

You would replace log4j.jar only if you wish to use a different logging 
implementation, say java.util.logging or logback. If you wish to stick with 
log4j, then stick to log4j.jar.

 > If I put the log4j jar back the app works (having restarted Tomcat),
 > but I think its using log4j not slf4j because I eventually get the
 > error
 >
 > java.lang.IncompatibleClassChangeError: Class org.apache.log4j.Logger
 > does not implement the requested interface org.slf4j.Logger

That's strange. Have you placed slf4j-api.jar and slf4j-log4j12.jar on the class 
path? If you have, which versions are you using?


-- 
Ceki Gülcü
Logback: The reliable, generic, fast and flexible logging framework for Java.
http://logback.qos.ch 
_______________________________________________
user mailing list
user at slf4j.org 
http://www.slf4j.org/mailman/listinfo/user


-- 
This message (and any attachments) is for the recipient only. NERC
is subject to the Freedom of Information Act 2000 and the contents
of this email and any reply you make may be disclosed by NERC unless
it is exempt from release under the Act. Any material supplied to
NERC may be stored in an electronic records management system.




More information about the slf4j-user mailing list