相关疑难解决方法(0)

在Java for String类中,有一个名为matches的方法,如何使用此方法检查我的字符串是否只使用正则表达式的数字.我试着用下面的例子,但是他们两个都把我弄错了.

String regex = "[0-9]";
String data = "23343453";
System.out.println(data.matches(regex));

String regex = "^[0-9]";
String data = "23343453";
System.out.println(data.matches(regex));

mysql> desc Student;
+---------+--------------+------+-----+---------+----------------+
| Field   | Type         | Null | Key | Default | Extra          |
+---------+--------------+------+-----+---------+----------------+
| Roll_no | int(11)      | NO   | PRI | NULL    | auto_increment |
| name    | varchar(200) | YES  |     | NULL    |                |
| address | varchar(200) | YES  |     | NULL    |                |
| phone   | int(100)     | YES  |     | NULL    |                |
| age     | int(11)      | YES  |     | NULL    |                |
+---------+--------------+------+-----+---------+----------------+
5 rows in set …