判断是否为纯数字拼接而成的字符串

    public static void main(String[] args) {        //8 表示每个数字的长度        Pattern pattern = Pattern.compile("([0-9]{8}[,]?)+");        String bigStr1 = "20170841,1";        String bigStr2 = "20170841,20170842";        Matcher isNum1 = pattern.matcher(bigStr1); // matcher是全匹配        //匹配返回true,否则返回false        System.out.println(isNum1.matches());        Matcher isNum2 = pattern.matcher(bigStr2); // matcher是全匹配        System.out.println(isNum2.matches());       }