【笔记】记一次因Spring版本和Tomcat版本不对应，造成Spring MVC项目启动后页面访问报404的问题

项目结构

pom.xml文件内容

xml 复制代码

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.dingli.chapter6</groupId>
    <artifactId>springmvc2</artifactId>
    <version>1.0-SNAPSHOT</version>
    <name>springmvc2</name>
    <packaging>war</packaging>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.target>17</maven.compiler.target>
        <maven.compiler.source>17</maven.compiler.source>
        <junit.version>5.11.0-M2</junit.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>jakarta.servlet</groupId>
            <artifactId>jakarta.servlet-api</artifactId>
            <version>6.1.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-engine</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>6.1.6</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.4.0</version>
            </plugin>
        </plugins>
    </build>
</project>

web.xml文件内容

xml 复制代码

<?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_6_0.xsd"
         version="6.0">

    <display-name>springmvc</display-name>
    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

        <!--配置初始化参数，指定Spring MVC的配置文件-->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:student.xml</param-value>
        </init-param>

        <!--启动时加载创建-->
        <load-on-startup>1</load-on-startup>

    </servlet>

    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

student.xml文件内容

xml 复制代码

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       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">

    <context:component-scan base-package="com.dingli.springmvc2" />

    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/studentpages/" />
        <property name="suffix" value=".jsp" />
    </bean>

</beans>

WelcomeController.java类

java 复制代码

package com.dingli.springmvc2;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
@RequestMapping("/user")
public class WelcomeController {

    @RequestMapping("/welcome")
    public String welcome() {
        return "welcome";
    }

    @RequestMapping(value = "/login", method = RequestMethod.GET)
    public String login() {
        return "login";
    }

}

welcome.jsp页面

html 复制代码

<%@ page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" language="java" %>
<html>
<head>
  <meta charset="UTF-8">
  <title>学生管理系统</title>

</head>
<body>
  <h1>欢迎来到登录页面！</h1>

</body>
</html>

login.jsp页面

html 复制代码

<%@ page contentType="text/html;charset=UTF-8" pageEncoding="UTF-8" language="java" %>
<html>
<head>
  <meta charset="UTF-8">
  <title>学生管理系统</title>

</head>
<body>
  <h1>欢迎来到登录页面！</h1>

</body>
</html>

启动

浏览器访问http://localhost:8080/springmvc2/user/welcome

原因：

Spring6版本，支持的是Tomcat10，而我本次部署的是Tomcat9版本的服务器，所以启动后访问失败。

从 Spring Framework 6.0 开始，Spring 已升级到 Jakarta EE 9 级别（例如 Servlet 5.0、JPA 3.0），基于 jakarta 命名空间而不是传统的 javax 包。由于 EE 9 是最低版本，并且已经支持 EE 10，Spring 准备为 Jakarta EE API 的进一步发展提供开箱即用的支持。Spring Framework 6.0 与 Tomcat 10.1、Jetty 11 和 Undertow 2.3 作为 Web 服务器完全兼容，并且还与 Hibernate ORM 6.1 完全兼容。

解决办法：

IDEA的Tomcat换成Tomcat10版本，再重新启动。

浏览器可以成功访问

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