code: public void checkForRotation() {
      try {
        BufferedReader probe = new BufferedReader(new FileReader(file.getAbsoluteFile()));
        if (firstLine == null || (!firstLine.equals(probe.readLine()))) {
  	probe.close();
  	// start reading the file from the beginning
          reader.close();
          reader = new BufferedReader(new FileReader(file.getAbsoluteFile()));
  	firstLine = null;
  	offset = 0;
        }
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
docs: Check whether the log file has been rotated. If so,
  start reading the file from the beginning.