入门级SpringMVC项目的创建

 

（01）为什么要用Spring框架

很多人都说学Java后必须学spring，spring框架为什么这么多人用？ - 知乎

  （02）完整流程的参考

https://blog.youkuaiyun.com/qq_45619623/article/details/118306300

（03）创建过程中几个重点(XML文件配置)

    3.1 POM.xml文件配置（特别是tomat的build配置）

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>org.example</groupId>
  <artifactId>MVC_1</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>MVC_1 Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>11</maven.compiler.source>
    <maven.compiler.target>11</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
      <scope>test</scope>
    </dependency>
<!--引入Spring MVC -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>5.3.1</version>
    </dependency>
  </dependencies>
<!--引入Tomcat服务器配置-->
  <build>
    <plugins>
       <plugin>
         <groupId>org.apache.tomcat.maven</groupId>
         <artifactId>tomcat7-maven-plugin</artifactId>
         <version>2.2</version>
         <configuration>
           <port>8080</port>
           <path>/</path>
         </configuration>
       </plugin>
    </plugins>
  </build>

</project> 

  3.2 前端XML文件的配置  web.xml

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>
  <servlet>
    <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.xml</param-value>
    </init-param>
  </servlet>
  <!-- 申明哪些请求会被我当前的Servlet处理-->
  <servlet-mapping>
    <servlet-name>springmvc</servlet-name>
    <!--
      1、带后缀的：*.action   *.do   *.aaa
      2、/  不会拦截JSP的
      3、/*  拦截所有，包括jsp（不建议，有些jsp没有具体后台处理）
    -->
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app> 

  3.3 后端XML文件配置  Springmvc.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/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">

    <!--开启Controller扫描-->
    <context:component-scan base-package="com.xiaolaodi.JavaDemo"></context:component-scan>
    <!--配置springmvc视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>
    <!--处理器映射器，处理器适配器-->
    <!--注册最合适的处理器适配器-->
    <mvc:annotation-driven></mvc:annotation-driven>
</beans> 

附注：SpringMVC的原理