以下是调试mvc源码过程中用到的demo以及配置文件
webapp/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

	<servlet>
		<servlet-name>springmvc</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath*:springmvc.xml</param-value>
		</init-param>
		<!-- load-on-startup元素标记容器是否在启动的时候就加载这个servlet(实例化并调用其init()方法) -->
		<load-on-startup>1</load-on-startup>
	</servlet>
	
	<servlet-mapping>
		<servlet-name>springmvc</servlet-name>
		<url-pattern>/</url-pattern>
	</servlet-mapping>
</web-app>

springmvc.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
        https://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
">


	<!--开启controller扫描-->
	<context:component-scan base-package="com.ocean.base.controller"/>
	<!--配置springmvc的视图解析器-->
	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/jsp/"/>
		<property name="suffix" value=".jsp"/>
	</bean>
	<!--
		自动注册最合适的处理器映射器，处理器适配器(调用handler方法)
	-->
	<!--<mvc:annotation-driven/>-->

</beans>

Controller

@Controller
@RequestMapping("/demo")
public class DemoController {


	@RequestMapping("/handle01")
	public String handle01(String name, Map<String, Object> model) {
		System.out.println("++++++++handler业务逻辑处理中....");
		Date date = new Date();
		model.put("date", date);
		return "success";
	}

	@RequestMapping("/index")
	public ModelAndView getModeAndView() {
		//创建一个模型视图对象
		ModelAndView mav = new ModelAndView("index");
		return mav;
	}
}

mvc调用的主流程

1. DispatcherServlet(前端控制器) 是个servlet，负责接收Request 并将Request 转发给对应的处理组件。
2. HanlerMapping （处理器映射器）是SpringMVC 中完成url 到Controller 映射的组件。DispatcherServlet 从HandlerMapping 查找处理Request 的Controller，
3. HanlerMapping 返回一个执行器链（url 到Controller 映射的组件）给DispatcherServlet
4. DispatcherServlet请求处理器适配器HandlerAdapter
5. 处理器适配器HandlerAdapter去访问我们的handler（controller）
6. handler（controller）返回ModelAndView给处理器适配器HandlerAdapter
7. 处理器适配器HandlerAdapter返回ModelAndView给DispatcherServlet
8. DispatcherServlet请求ViewResolver视图解析器
9. ViewResolver视图解析器返回view给DispatcherServlet
10. DispatcherServlet请求view做页面解析和渲染
11. view将渲染好的数据返回给DispatcherServlet，DispatcherServlet将渲染好的字符流给client，看到了页面！