code: public static String unicodeToString(String s) {
          StringBuilder sb = new StringBuilder();
          StringTokenizer st = new StringTokenizer(s, "\\u");
          while (st.hasMoreTokens()) {
              String token = st.nextToken();
              if (token.length() > 4) {
                  sb.append((char) Integer.parseInt(token.substring(0, 4), 16));
                  sb.append(token.substring(4));
              } else {
                  sb.append((char) Integer.parseInt(token, 16));
              }
          }
          return sb.toString();
      }
docs: Convert a string that is unicode form to a normal string.
  
  @param s The unicode form of a string, e.g. "\\u8001\\u9A6C"
  @return Normal string