public static String halfWidthToFullWidth(String s) {
        if (isEmpty(s)) {
            return s;
        }

        char[] source = s.toCharArray();
        for (int i = 0; i < source.length; i++) {
            if (source[i] == ' ') {
                source[i] = (char)12288;
                // } else if (source[i] == '.') {
                // source[i] = (char)12290;
            } else if (source[i] >= 33 && source[i] <= 126) {
                source[i] = (char)(source[i] + 65248);
            } else {
                source[i] = source[i];
            }
        }
        return new String(source);
    }