老师，出现了错误[ The markup in the document following the root element must be well-formed ]
<?xml version="1.0" encoding="UTF-8"?>
<servlet>
<servlet-name>我的第一个servlet</servlet-name>
<servlet-class>servlet.Hello_servlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>我的第一个servlet</servlet-name>
<url-pattern>/servlet/Hello_servlet</url-pattern>
</servlet-mapping>
