1.DispatcherServlet：前端控制器，用于接收请求。(即spring mvc是基于servlet实现的所以要注意多线程问题)
2.HandlerMapping接口：DefaultAnnotationHandlerMapping :HandlerMapping接口的实现, 用于处理请求的映射。即前端请求找到对应的controller
3.HandlerAdapter接口：AnnotationMethodHandlerAdapter: HandlerAdapter接口的实现，用于处理请求的映射。根据前端请求找到controller的方法
4.ViewResolver接口：InternalResourceViewResolver : ViewResolver接口的实现，用于把ModelAndView的逻辑视图名解析为具体的View。
前端请求过来，通过DefaultAnnotationHandlerMapping(注解) 找到对应的Controller，然后通过AnnotationMethodHandlerAdapter找到处理请求的方法，方法处理完后，通过InternalResourceViewResolver返回到哪个视图；
配置文件：
<?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:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <!-- 匹配请求和Controller有两种写法 --> <!-- 第一种请求直接对应Controller类(默认使用) --> <!-- BeanNameUrlHandlerMapping --> <!-- <bean id="/hello" class="com.controller.HelloController"></bean> <bean id="/hello_2" class="com.controller.HelloController_2"></bean> --> <!-- 第二种Controller类标注自己的id，然后通过HandlerMapping集体对应 --> <!-- SimpleUrlHandlerMapping --> <!-- <bean id="helloController" class="com.controller.HelloController"></bean> <bean id="helloController_2" class="com.controller.HelloController_2"></bean> <bean id="simpleUrlHandlerMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <property name="mappings"> <props> <prop key="/helloTest_2">helloController_2</prop> <prop key="/helloTest">helloController</prop> </props> </property> </bean> --> <!-- 一个Controller写多个方法 --> <bean id="paramMethodResolver" class="org.springframework.web.servlet.mvc.multiaction.ParameterMethodNameResolver"> <property name="paramName" value="action"></property> </bean> <bean name="/multi" class="com.controller.MultiController"> <property name="methodNameResolver"> <ref bean="paramMethodResolver"/> </property> </bean> <!-- 注解映射方式 --> <mvc:annotation-driven /> <!-- 如果当前请求为“/”时，则转发到“/helloworld/index” --> <mvc:view-controller path="/" view-name="forward:/annotationController/helloworld" /> <!-- 开启controller注解支持 --> <!-- use-default-filters="false" 只扫描指定的注解 --> <context:component-scan base-package="com.controller" use-default-filters="false"> <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" /> </context:component-scan> <!-- 视图解析器 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> <property name="contentType" value="text/html" /> <property name="prefix" value="/WEB-INF/views/" /> <property name="suffix" value=".jsp" /> </bean> <!-- 支持上传文件 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 设置上传文件的最大尺寸为1MB --> <property name="maxUploadSize"> <value>1048576</value> </property> <property name="defaultEncoding"> <value>UTF-8</value> </property> </bean> </beans>
Controller实现：
package com.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.mvc.AbstractController; /** * 一个类一个Controller,一个请求 */ public class HelloController extends AbstractController{ @Override protected ModelAndView handleRequestInternal(HttpServletRequest arg0, HttpServletResponse arg1) throws Exception { System.out.println("............HelloController................."); return new ModelAndView("index"); } }
package com.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.mvc.AbstractController; public class HelloController_2 extends AbstractController{ @Override protected ModelAndView handleRequestInternal(HttpServletRequest arg0, HttpServletResponse arg1) throws Exception { System.out.println("............HelloController_2................."); return new ModelAndView("index"); } }
一个类一个Controller，可以对应多个请求:
package com.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.mvc.multiaction.MultiActionController; /** * 一个类一个Controller，可以对应多个请求 *在一个Controller类中定义多个方法，并根据使用者的请求来执行当中的某个方法， *相当于Struts的DispatcherAction。 *使用MultiActionController需要配个MethodNameResolver实例， *默认使用ParameterMethodNameResolver，他会根据所给的网址中， *最后请求的文件名称来判断执行Controller中的哪一个方法 * *MultiActionController 也实现了AbstractController类,实现了handleRequestInternal方法 * @Override protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response) throws Exception { try { //通过请求找到方法名 String methodName = this.methodNameResolver.getHandlerMethodName(request); //然后调用具体的方法(注意＊＊＊＊参数：request，response＊＊＊＊＊＊＊＊) return invokeNamedMethod(methodName, request, response); } catch (NoSuchRequestHandlingMethodException ex) { return handleNoSuchRequestHandlingMethod(ex, request, response); } } */ public class MultiController extends MultiActionController{ public String add(HttpServletRequest request, HttpServletResponse response){ System.out.println("-----------add------------"); return "index"; } public String delete(HttpServletRequest request, HttpServletResponse response){ System.out.println("------------delete--------------"); return "index"; } public String update(HttpServletRequest request, HttpServletResponse response){ System.out.println("---------------update---------------"); return "index"; } }
基于注解实现Controller：
package com.controller; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.servlet.ModelAndView; @Controller @RequestMapping(value = "annotationController") public class AnnotationController { @RequestMapping(value = "/helloworld", method = { RequestMethod.GET }) protected ModelAndView helloworld() { System.out.println("............HelloController_3................."); return new ModelAndView("index"); } }
WebContent/views/下的视图：
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> hello word!!! </body> </html>