title: How to detectd that log4j not is not properly initialized
body: <p>I know that when neither log4j.properties nor log4j.xml is found on the classpath, we got a </p>
  
  <pre><code>log4j:WARN No appenders could be found for logger (xxx).
      log4j:WARN Please initialize the log4j system properly.
  </code></pre>
  
  <p>How can I detect that in java so that I could execute some custom code? Example: to print something to my user?</p>