SpringMVC框架（一）

SpringMVC最核心：DispatcherServlet

SpringMVC环境搭建：

结构：

过程：

　　1.导包

　　2.声明SpringMVC核心Servlet：org.springframework.web.servlet.DispatcherServlet

　　　　声明Spring配置文件的路径：

　　　　　　1.可以自己声明

　　　　　　2.默认值：/WEB-INF/springDispatcherServlet-servlet.xml

　　3.新建Spring配置文件

　　　　（注解方式）

　　　　1.扫描器：<context:component-scan base-package="com.maya"></context:component-scan>

　　　　2.配置视图解析器，设置前缀后缀

　　　　3.开启SpringMVC注解驱动：<mvc:annotation-driven></mvc:annotation-driven>

　　　　4.编写控制器类，声明方法

　　　　5.运行页面

代码：

web.xml：

 <?xml version="1.0" encoding="UTF-8"?>
 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
   <display-name>test_easyui2</display-name>

 <!-- The front controller of this Spring Web application, responsible for handling all application requests -->
     <servlet>
         <servlet-name>springDispatcherServlet</servlet-name>
         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
         <!-- 初始化参数，如果不写有默认值，/WEB-INF/springDispatcherServlet-servlet.xml -->
         <init-param>
             <param-name>contextConfigLocation</param-name>
             <param-value>classpath:spring-mvc.xml</param-value>
         </init-param>
         <!-- 值大于0时，启动服务器时加载，数字越小，优先级越高 -->
         <load-on-startup>1</load-on-startup>
     </servlet>

     <!-- Map all requests to the DispatcherServlet for handling -->
     <servlet-mapping>
         <servlet-name>springDispatcherServlet</servlet-name>
         <url-pattern>/</url-pattern>
     </servlet-mapping>
 </web-app>

spring-mvc.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/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
         http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">

     <!-- <bean id="/helloworld" class="com.maya.controller.HelloWorldController"></bean>

     spring2.5之前的配置方式
     将SpringBean的名字作为映射路径的请求
     <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>
     处理适配器，将请求映射给conntroller类
     <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>
     视图解析器
     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"></bean>
      -->

      <!-- 注解方式 -->
      <!-- 扫描器 -->
     <context:component-scan base-package="com.maya"></context:component-scan>
     <!-- 视图解析器 -->
     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
         <property name="prefix" value="/page/"></property>
         <property name="suffix" value=".jsp"></property>
     </bean>
     <!-- 开启springmvc注解驱动 -->
     <mvc:annotation-driven></mvc:annotation-driven>

 </beans>

两种处理方式类：

 package com.maya.controller;

 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.springframework.web.servlet.ModelAndView;
 import org.springframework.web.servlet.mvc.Controller;

 //只能处理单一请求
 public class HelloWorldController implements Controller {

     @Override
     public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
         ModelAndView mav=new ModelAndView();
         mav.setViewName("page/success.jsp");

         mav.addObject("message","测试，属性message");
         //以上方法等同于request.setAttribute(arg0, arg1);
         return mav;
     }

 }

注解方式：

 package com.maya.controller;

 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.servlet.ModelAndView;

 @Controller
 public class TestController {

     @RequestMapping("/testHelloWorld")
     public ModelAndView testHelloWorld(){
         ModelAndView mav=new ModelAndView();
         mav.addObject("msg", "测试属性msg");
         mav.setViewName("success");
         return mav;
     }
 }

jsp页面：

 <%@ 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>
     <div>
         <span>spring 2.5 之前</span>
         <a href="helloworld">传送门</a>
     </div>
     <div>
         <span>基于注解</span>
         <a href="testHelloWorld">传送门2</a>
     </div>
 </body>
 </html>

 <%@ 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>
     <h1>成功！！！</h1>
     ${message }
     ${msg }
 </body>
 </html>

常用注解：

@Controller　　声明控制器类

@RequestMapping　　声明映射的请求

@RequestParam　　参数绑定

@PathVariable　　绑定路径参数

@ResponseBody　　将方法的返回值直接返回

@SessionAttribute　　将指定的对象放到session

@ModelAttribute