code: public static String createFile(String fn){
  		File file = new File(fn);
  		try {
  			file.createNewFile();
  		}
  		catch (IOException e) {
  			return e.getMessage();
  		}
  		return null;
  	}
docs: Creates a file for a given absolute file name (absolute path and file name).
  @param fn absolute file name
  @return null on success, error string otherwise