title: Method should call once and only once in its lifecycle
body: <p>I have a method which is actually a scheduler which runs a process in every one hour and create a log file every hour.<br/>
  I want to call this method once in the application life cycle so I call it from a static block.<br/> But I feel this is not working because the file is sometimes generated in one hour and sometimes early. I heard somewhere that static block only execute once is it not true?<br/>
  If yes than what should I do?</p>