public static String htmlEscape(String text) {
        if (text == null)
            return "";
        StringBuilder res = null;
        int len = text.length();
        int i;
        for (i = 0; i < len; ++i) {
            switch (text.charAt(i)) {
                case '<':
                case '>':
                case '&':
                case '\r':
                case '\n':
                    res = new StringBuilder(text.substring(0, i));
                    break;
                default:
                    continue;
            }
            break;
        }
        if (res == null)
            return text; // no replacement needed
        for (; i < len; ++i) {
            char ch = text.charAt(i);
            switch (ch) {
                case '<':
                    res.append("<");
                    break;
                case '>':
                    res.append(">");
                    break;
                case '&':
                    res.append("&");
                    break;
                case '\r':
                case '\n':
                    res.append("<br>\n");
                    break;
                default:
                    res.append(ch);
                    break;
            }
        }
        return res.toString();
    }