private String convert2(String source){
    char c1='u007F';
    return Character.toString(c1);
}

private String convert2(String source){
    char c2='u0080';
    return Character.toString(c1);
}

public static String hexStringToString(String s) {
    int len = s.length();
    char[] data = new char[len / 2];
    for (int i = 0; i < len; i += 2) {
        data[i / 2] = (char) (
                (Character.digit(s.charAt(i), 16) << 4)
                + Character.digit(s.charAt(i+1), 16)
        );
    }
    return new String(data);
}