private boolean isANumber(String s){
        boolean isNumeric =false;
        if (s != null && !s.equals("")){
            isNumeric=true;
            char chars[] = s.toCharArray();
            for (int i=0;i<chars.length;i++){
                isNumeric &= Character.isDigit(chars[i]);
                if (!isNumeric && chars[i]!='.')
                    return false;
                if (chars[i]=='.')
                    isNumeric=true;
            }
        }
        return isNumeric;
    }