When learning the springMVC framework, I encountered some problems about Tomcat.
The first one: this error java.lang.IllegalArgumentException: Unsupported class file major version 59. It is because of version incompatibility, just try to lower the jdk version. 
The second problem is: the "Bean" element declaration cannot be found
```xml
<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
https://www.springframework.org/schema/mvc/spring-mvc.xsd">
Error in the head of the configuration xml file. It's better to go to the official website to assign the value to the notes. The error rate of typing by hand is higher than that of copying.