private String makeUnicodeCharactersEscaped(String str) {
        StringBuilder b = new StringBuilder();

        for (char c : str.toCharArray()) {
            if ((1024 <= c && c <= 1279) || (1280 <= c && c <= 1327) || (11744 <= c && c <= 11775) || (42560 <= c && c <= 42655)) {
                b.append("\\u").append("0").append(Integer.toHexString(c));
            } else {
                b.append(c);
            }
        }

        return b.toString();
    }