springMVC的使用方式

1.通过maven引入相关的jar包依赖

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>5.2.6.RELEASE</version>
    </dependency>

2.在web.xml中配置DispatcherServlet

  <servlet>
    <servlet-name>springMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>    <!--配置spring配置文件的路径-->
      <param-value>classpath:springMVC.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>springMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

3.配置spring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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

<!--开启包扫描-->
    <context:component-scan base-package="com.yzy"></context:component-scan>

<!--配置视图解析器 找到对应的jsp页面-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!--配置前缀匹配符        -->
        <property name="prefix" value="/"></property>
<!--配置后缀匹配符        -->
        <property name="suffix" value=".jsp"></property>
    </bean>
</beans>

4.根据需求编写对应的handler类

package com.yzy.controller;


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

import java.util.Map;

@Controller("testHandler")
public class testHandler {

//    通过Model来实现数据封装传输，最后以字符串的形式返回要将数据返回至对应的页面（view）
    @RequestMapping("/ModelTest")
    public String ModelTest(Model model){
        //此操作相当于在servlet中request.setAttribute("name","model"),下面方法也是如此
        model.addAttribute("name","model");   
        return "index";
    }
    //    通过Map来实现数据封装传输，最后以字符串的形式返回要将数据返回至对应的页面（view）
    @RequestMapping("/MapTest")
    public String MapTest(Map<String,String> map){
        map.put("name","map");
        return "index";
    }
    //    通过ModelAndView来实现数据封装传输，将数据返回至对应的页面（view）同时也封装在此对象中的viewName中
    @RequestMapping("/ModelAndViewTest")
    public ModelAndView ModelAndViewTest(){
        ModelAndView modelAndView=new ModelAndView();
        modelAndView.addObject("name","modelAndView");
        modelAndView.setViewName("index");
        return modelAndView;
    }


}

注意：在web.xml中配置DispatcherServlet时，会使css的样式文件也进入到此servlet来，导致无法正常显示样式，应如下在web.xml中添加设置，使css进入默认的servlet

  <servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.css</url-pattern>
  </servlet-mapping>

在web.xml中配置DispatcherServlet