Best practices for Java logging from multiple threads?

Question

I want to have a diagnostic log that is produced by several tasks managing data. These tasks may be in multiple threads. Each task needs to write an element (possibly with s

Answer 1

Use a logging framework, such as Log4.

and if you are not happy with the output you can write your own Appender, Filter, whatever to tweak it just write. So you could do even some caching to rearrange the entries, although I am not saying this is a good idea.