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Is it fine to do logs in java class with thread id?

When we add logs in to the java class (using log4j), Is it fine to add thread id with that log messages? is it a bad practice? My idea was to add this thread id; Once we examine a log file of a multithreaded application, it is difficult to find out the correct flow using logs. (As an example, say authentication flow). Is there any better approach for this rather than logging thread id?

Answer

Log4j already supports the thread name using t placeholder in its pattern layout. So this is a supported feature that you should use if you find it useful. This way you don’t need to pass the thread name manually. However it doesn’t make use of the thread ID. So you should give meaningful names to your threads. This should be preferred as it is more indicative to what is going on in your application than just plain thread ids.