dispatherServlet攔截所有請求，但是不攔截JSP和其他配置的servelt

不是順序問題，是就不攔截Servlet

不是load-on-startup啟動先后順序問題，是就是不攔截Servlet。

SpringMVC默認用的是第二個

//<url-pattern>/*</url-pattern>會攔截JSP，靜態文件，不攔截Servlet，攔截陌生URL
//<url-pattern>/</url-pattern>攔截靜態文件，不攔截JSP和Servlet，攔截陌生URL
public class MyDispatcherServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println(req.getRequestURI());
    }
}

<servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>servlet.MyDispatcherServlet</servlet-class>
    <load-on-startup>-1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/*</url-pattern>
</servlet-mapping>
<servlet>
    <servlet-name>JsonServlet</servlet-name>
    <servlet-class>servlet.JsonServlet</servlet-class>
    <load-on-startup>10</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>JsonServlet</servlet-name>
    <url-pattern>/getJson</url-pattern>
</servlet-mapping>