java正则表达式验证金额

String reg_money = "\\d+(\\.\\d{1,2})?";// 金额正则,可以没有小数，小数最多不超过两位
        Pattern pattern = Pattern.compile(reg_money);
        Matcher matcher = pattern.matcher("5566.21");
        boolean ismatch = matcher.matches();
        System.out.println(ismatch);