SpringMVC工作流程

1、用户向服务器发送请求，被SpringMvc前端控制器DispatcherServlet捕获。

<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:dispatcher-servlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>springmvc</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

2、DispatcherServlet对请求URL进行解析，得到URI，根据URI调用HandlerMapping获得Handler配置的所有相关对象

3、DispatcherServlet根据获得的Handler，选择一个合适的HandlerAdapter。提取request中的模型数据，填充handler入参，开始执行Handler(Controller)

4、Handler执行完成后，向DispatcherServlet返回一个ModelAndView对象

@RequestMapping(value = "/dashboard")
public class DashboardCtrl extends AbsBaseCtrlAware {

    private static final Logger logger = Logger.getLogger("LoginCtrl");

    @Resource(name = "userService")
    private UserService userService;

    @RequestMapping
    public ModelAndView into(HttpServletRequest request) {
        RealTimeUserInfo realTimeUserInfo = userService.getRealTimeUserInfoByUser(getCurrentUser());
        ModelAndView ret = new ModelAndView("main/main");
        Map<String, Date> priod = userService.getPriod(getCurrentUser());
        if (priod != null && priod.containsKey("billStart") && priod.containsKey("billEnd")) {
            ret.addObject("spriod", StringUtil.formatDate(priod.get("billStart"), "yyyy-MM-dd"));
            ret.addObject("epriod", StringUtil.formatDate(priod.get("billEnd"), "yyyy-MM-dd"));
        }
        ret.addObject("userInfo", realTimeUserInfo);
        // 功能权限刷新
        request.getSession().setAttribute("openFunction", OpenFunctionUtil.getSinglton());
        request.getSession().setAttribute("nav", "dashboard");
        return ret;
    }
}

5、DispatcherServlet根据返回的ModelAndView，选择一个合适的ViewResolver，渲染视图，返回客户端

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/page/"/>
    <property name="suffix" value=".jsp"/>
    <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
</bean>

6、拦截器会对全部/部分url进行拦截

<!-- 拦截器 -->
<mvc:interceptors>
    <bean class="com.selfpackage.interceptor.AuthorizeInterceptor"/>
    <bean class="com.selfpackage.interceptor.Idstar30Interceptor"/>
    <bean class="com.selfpackage.interceptor.CasSsoInterceptor"/>
    <bean class="com.selfpackage.interceptor.LoginInterceptor"/>
    <bean class="com.selfpackage.interceptor.CsrfInterceptor"/>
    <bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"/>
</mvc:interceptors>