docs: private char readEscapeCharacter() throws JSONException {
          char escaped = in.charAt(pos++);
          switch (escaped) {
              case 'u':
                  if (pos + 4 > in.length()) {
                      throw syntaxError("Unterminated escape sequence");
                  }
                  String hex = in.substring(pos, pos + 4);
                  pos += 4;
                  try {
                      return (char) Integer.parseInt(hex, 16);
                  } catch (NumberFormatException nfe) {
                      throw syntaxError("Invalid escape sequence: " + hex);
                  }
  
              case 't':
                  return '\t';
  
              case 'b':
                  return '\b';
  
              case 'n':
                  return '\n';
  
              case 'r':
                  return '\r';
  
              case 'f':
                  return '\f';
  
              case '\'':
              case '"':
              case '\\':
              default:
                  return escaped;
          }
      }