private String getChar_code(String str) {
        myDataList mytable = (myDataList) arrList.get(0);

        for (int i = 0; i < mytable.size(); i++) {
            if (((data) mytable.get(i)).getChar().equals(str)) {
                return (((data) mytable.get(i)).getBinary_Code());
            }
        }
        return "??";
    }