code: public static FileLogHolder createFileLogHolder(TraceWriter oldLog, FileLogHeader logHeader,
                                                      File logDirectory, String newFileName,
                                                      int maxFiles, long maxSizeBytes) {
          return createFileLogHolder(oldLog, logHeader, logDirectory, newFileName, maxFiles, maxSizeBytes, NEW_LOGS_ON_START_DEFAULT);
      }
docs: This method will check to see if the supplied parameters match the settings on the <code>oldLog</code>,
  if they do then the <code>oldLog</code> is returned, otherwise a new FileLogHolder will be created.
  
  @param oldLog The previous FileLogHolder that may or may not be replaced by a new one, may
  be <code>null</code> (will cause a new instance to be created)
  @param logHeader
  Header to print at the top of new log files
  @param logDirectory
  Directory in which to store created log files
  @param newFileName
  File name for new log: this will be split into a name and extension
  @param maxFiles
  New maximum number of log files. If 0, log files won't be pruned.
  @param maxSizeBytes
  New maximum log file size in bytes. If 0, log files won't be rolled.
  @return a log holder. If all values are the same, the old one is returned, otherwise a new log holder is created.