code: public Reader getFile(String prefix, String postfix)
        throws MtasParserException {
      String file = getString();
      if ((file != null) && !file.equals("")) {
        if (prefix != null) {
          file = prefix + file;
        }
        if (postfix != null) {
          file = file + postfix;
        }
        Path path = (new File(file)).toPath();
        if(Files.isReadable(path)) {
          try {
            return new InputStreamReader(new GZIPInputStream(new FileInputStream(file)), StandardCharsets.UTF_8);
          } catch (IOException e1) {
            log.debug(e1);
            try {
              String text = new String(Files.readAllBytes(Paths.get(file)),
                  StandardCharsets.UTF_8);
              return new StringReader(text);
            } catch (IOException e2) {
              log.debug(e2);
              throw new MtasParserException(e2.getMessage());
            }
          } 
        } else {
          throw new MtasParserException("file '"+file+"' does not exists or not readable");
        }
      } else {
        throw new MtasParserException("no valid file: " + file);
      }
    }
docs: Gets the file.
  
  @param prefix the prefix
  @param postfix the postfix
  @return the file
  @throws MtasParserException the mtas parser exception