Display thread id instead thread name in log

Question

I have a Struts application with log4j to display information about application.

The pattern to format log\'s output is as follows:

log4j.appender.RA         


        

Answer 1

One way you can do it is to add it yourself using log4j MDC. We use it for adding the username for web requests. We do this in a filter at the start of each request. Eg.

import org.apache.log4j.MDC;

...

  // Add username to MDC
  String username = ...;
  MDC.put("user", username);

Then add [%X{user}] to your conversion pattern.