<servlet>
<servlet-name>spring-mvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
<servlet-name>spring-mvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
load-on-startup can specify an (optional) integer value. If the value is 0 or greater, it indicates an order for
servlets to be loaded, servlets with higher numbers get loaded after servlets with lower numbers.
load-on-startup指定一个整数值，说明sevelet载入顺序，数值越大载入顺序越靠后
