public static void writeln(final BufferedWriter w, final String s) {
    try {
      if (s == null) {
        w.write("");
      }
      else {
        w.write(s);
      }
      w.newLine();
    }
    catch (IOException e) {
      throw new BuildDataCorruptedException(e);
    }
  }
public static void writeln(final BufferedWriter w, final String s)