MVC环境搭建

1.引入依赖

  <!-- 集成 spring 框架 --><dependency><groupId>org.springframework</groupId><artifactId>spring-core</artifactId><version>5.2.13.RELEASE</version></dependency><!-- 集成 web 框架 --><dependency><groupId>org.springframework</groupId><artifactId>spring-web</artifactId><version>5.2.13.RELEASE</version></dependency><!-- SpringMVC --><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.2.13.RELEASE</version></dependency>

2. 修改项目web-inf下的web.xml

<web-app><display-name>Archetype Created Web Application</display-name><!--配置过滤器 解决中文乱码问题--><filter><filter-name>CharacterEncodingFilter</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><!--初始化CharacterEncodingFilter类时所需要的参数--><init-param><param-name>encoding</param-name><param-value>utf-8</param-value></init-param><!--响应的字符集也强制按照设置的encoding--><init-param><param-name>forceResponseEncoding</param-name><param-value>true</param-value></init-param></filter><!--表示过滤器对哪些请求生效 匹配请求地址--><filter-mapping><filter-name>CharacterEncodingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping><servlet><!--配置springmvc框架入口--><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-servlet.xml</param-value></init-param><!--在项目启动时就创建 默认为在使用时创建--><load-on-startup>1</load-on-startup></servlet><!--另一种映射方式--><!--    &lt;!&ndash;声明 servlet &ndash;&gt;--><!--    <servlet>--><!--        <servlet-name>test</servlet-name>--><!--        <servlet-class>com.j3071.mvc.servlet.TestServlet01</servlet-class>--><!--    </servlet>--><!--    &lt;!&ndash;建立 servlet 映射&ndash;&gt;-->
<!--    <servlet-mapping>-->
<!--        <servlet-name>test</servlet-name>-->
<!--        <url-pattern>/test</url-pattern>-->
<!--    </servlet-mapping>--><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>/</url-pattern></servlet-mapping></web-app>

3.在resources目录下添加 springMVC-servlet.xml 内容如下

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:context="http://www.springframework.org/schema/context"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc.xsd"><!--基于beanname的方式-->
<!--    <bean name="/testmvc" class="com.j3071.mvc.controller.BeanNameController"></bean>--><!--注解映射的方式--><context:component-scan base-package="com.j3071.mvc.controller"/><!--配置注解驱动--><mvc:annotation-driven/><!--配置解析物理地址的方式--><bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"><property name="prefix" value="/"/><!--jsp的路径 如果在jsp包下 /jsp/--><property name="suffix" value=".jsp"/><!--后缀--></bean>
</beans>

4.编写controller

package com.j3071.mvc.controller;/** @Date:2023/11/16* @Description:com.j3071.mvc.controller*/import com.alibaba.fastjson.JSONObject;
import com.j3071.mvc.entity.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;@Controller
public class AnnController {//设置映射路径@RequestMapping("/testAnn")public ModelAndView m1(){ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");return modelAndView;}@RequestMapping("/testAnn1")public ModelAndView m2(@RequestParam("userName") String userName,@RequestParam("passWord") String passWord){System.out.println(userName);System.out.println(passWord);ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");return modelAndView;}@RequestMapping("/testAnn2")public ModelAndView m3(User user){System.out.println(user.getUserName());System.out.println(user.getPassWord());ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");//设置返回的数据 作用于req.setAttribute()一样modelAndView.addObject("message","登陆成功");return modelAndView;}/*** 如何返回json数据* @return*/@RequestMapping("/testJson")@ResponseBodypublic String m4(){User user=new User();user.setUserName("张三");user.setPassWord("123456");//方法返回值是String时 默认为返回的是页面 如果想返回String数据本身那么使用@ResponseBody注解//return "test01";return JSONObject.toJSONString(user);}
}

5.Controller接收参数

@Controller
public class AnnController {//按参数来接收@RequestMapping("/testAnn1")public ModelAndView m2(@RequestParam("userName") String userName,@RequestParam("passWord") String passWord){System.out.println(userName);System.out.println(passWord);ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");return modelAndView;}//按对象来接收@RequestMapping("/testAnn2")public ModelAndView m3(User user){System.out.println(user.getUserName());System.out.println(user.getPassWord());ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");//设置返回的数据 作用于req.setAttribute()一样modelAndView.addObject("message","登陆成功");return modelAndView;}}

6.处理form请求 返回ModelAndView

  @RequestMapping("/testAnn2")public ModelAndView m3(User user){System.out.println(user.getUserName());System.out.println(user.getPassWord());ModelAndView modelAndView=new ModelAndView();modelAndView.setViewName("test01");//设置返回的数据 作用于req.setAttribute()一样modelAndView.addObject("message","登陆成功");return modelAndView; }

7.处理ajax请求返回json数据 添加@ResponseBody注解

  /*** 如何返回json数据* @return*/@RequestMapping("/testJson")@ResponseBodypublic String m4(){User user=new User();user.setUserName("张三");user.setPassWord("123456");//方法返回值是String时 默认为返回的是页面 如果想返回String数据本身那么使用@ResponseBody注解//return "test01";return JSONObject.toJSONString(user);}