code: public static KieRuntimeLogger newFileLogger(KieRuntimeEventManager session,
                                                         String fileName) {
          return getKnowledgeRuntimeLoggerProvider().newFileLogger( session,
                                                                    fileName );
      }
docs: Creates a file logger in the current thread. The file is in XML format, suitable for interpretation by Eclipse's Drools Audit View
  or other tools. Note that while events are written as they happen, the file will not be flushed until it is closed or the underlying
  file buffer is filled. If you need real time logging then use a Console Logger or a Threaded File Logger.
  
  @param session
  @param fileName - .log is appended to this.
  @return