SpringMVC工作流程

SpringMVC基本使用

xml模式(麻烦，不推荐)

1.1导入依赖

在pom.xml中添加spring-mvc，servlet，jsp的依赖：

<dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.6.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>javax.servlet.jsp-api</artifactId>
            <version>2.3.3</version>
        </dependency>

添加了spring-webmvc依赖之后，其他的spring-web,sping-aop,spring-context等等就全部加进来了

1.2配置核心(前端)控制器

web.xml中配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee https://jakarta.ee/xml/ns/jakartaee/web-app_5_0.xsd"
         version="5.0">
<!--配置DispatcherServlet：SpringMVC的核心；请求分发器，前端控制器-->
<servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!--绑定SpringMVC的配置文件-->
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:springmvc-servlet.xml</param-value>
    </init-param>
    <!--启动级别  饿汉，懒汉式加载-->
    <load-on-startup>1</load-on-startup>
</servlet>
    <!--
         在SpringMVC中，/ ,/*
         /:只匹配所有的请求，不匹配静态资源，会覆盖掉TOMCAT原本的默认Servlet
         /*:匹配所有的请求，包括静态资源
    -->
<servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
</servlet-mapping>
<!-- 配置SpringMVC的乱码过滤-->
    <filter>
        <filter-name>encoding</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encoding</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

1.3配置文件

resources文件夹下建立对应配置文件，根据前端控制器绑定的配置文件名

新建 springmvc-servlet.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:p="http://www.springframework.org/schema/p"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">
<!--处理器映射器-->
    <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>
<!--处理器适配器-->
    <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>
<!--视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="InternalResourceViewResolver">
        <!--前缀-->
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <!--后缀-->
        <property name="suffix" value=".jsp"/>
    </bean>
    <!--3.配置控制器     相当于配置了访问路径 -->
    <bean id="/hello" class="com.peppa.web.HelloController"/>
</beans>

1.4后端控制器

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

public class HelloController implements Controller {

    @Override
    public ModelAndView handleRequest(javax.servlet.http.HttpServletRequest httpServletRequest, javax.servlet.http.HttpServletResponse httpServletResponse) throws Exception {
        ModelAndView modelAndView = new ModelAndView();
        //业务代码
        String  result="HelloSpringMVC";
        modelAndView.addObject("msg",result);
        //视图跳转
        modelAndView.setViewName("test");

        return modelAndView;
    }
}

1.5访问

注解模式(推荐)

导jar和web.xml的步骤是一样的,不一样的地方在于主配置文件和控制层的代码

贴上注解模式的主配置文件

<?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"
       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/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">
<!--配置注解扫描位置-->
    <context:component-scan base-package="com.peppa.web.controller"/>
<!--省去处理器和映射器配置，注解配置驱动-->
    <mvc:default-servlet-handler/>
    <mvc:annotation-driven/>
<!--视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="InternalResourceViewResolver">
        <!--前缀-->
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <!--后缀-->
        <property name="suffix" value=".jsp"/>
    </bean>
</beans>

控制层的代码

@Controller //控制器
@RequestMapping("/Hello") //这个是为了分清模块
public class StudentController {
 
    @RequestMapping("/test1")    //链接名
    public String list(){
        System.out.println(1);
        return "/index";    //返回的页面
    }
    //这个为ajax的套路
    @RequestMapping("/test2")
    public void list2(HttpServletRequest request, HttpServletResponse response) throws IOException {
        String str=JSON.toJSONString("ssssss");
        response.getWriter().println(str);
        response.getWriter().flush();
        response.getWriter().close();
    }
}

本文地址：https://blog.csdn.net/qq_44073614/article/details/111838085