spring 配置jndi 报错 Cannot create JDBC driv?报错

Spring 配置jndi

我的代码如下，首先tomcat配置jndi

1、tomcat lib包下引入连接mysql数据库驱动

2、在tomcat config 下的content.xml下配置全局数据库信息

<Resource name="jdbc/mysql"
                  auth="Container"
                  type="javax.sql.DataSource"
                  driverClassName="com.mysql.jdbc.Driver"
                  maxWait="5000"
                  username="root"
                  password="1234"
                  testOnBorrow="true"
                  url="jdbc:mysql://172.20.8.90:3306/test"
        />

<resource-ref>
        <res-ref-name>jdbc/mysql</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
	</resource-ref>

<bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">  
		        <property name="jndiName">  
		            <value>java:comp/env/jdbc/mysql</value>  
		        </property>  
		    </bean>

5、在项目的METE-INF下面创建content.xml，信息如下

 <?xml version='1.0' encoding='utf-8'?>
    <Context>
    <Resource name="jdbc/mysql"
                  auth="Container"
                  type="javax.sql.DataSource"
                  driverClassName="com.mysql.jdbc.Driver"
                  maxWait="5000"
                  username="root"
                  password="1234"
                  testOnBorrow="true"
                  url="jdbc:mysql://172.20.8.90:3306/test"
        />
</Context>

<p>
	<br>
</p>
<p>
	<br>
</p>

项目启动 不报错，但是我请求http://localhost:8080/hello-mybatis/hello/test.do

报错： org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'] with root cause

代码如下

@Controller
@RequestMapping("/hello")
public class HelloWorldController {

    @Autowired
    private UserMapper userMapper;

    @RequestMapping("/test.do")
    public String test() {
        User user = this.userMapper.selectByPrimaryKey(1);
        System.out.println(user.getName());
        return "test";
    }

}

我可以确认我的配置信息是正确的，url、user、password、driver都正确