Spring MVC 和 Maven（404 错误：资源）

Question

这是我认为我配置正确的文件。我的 Tomcat 9 应用程序已启动并正常运行。我只是不知道这是什么问题。 Tomcat 部署应用程序，但我不确定问题是否在 Tomcat 或 Spring MVC 上出现

rcontroller.java:

package com.mycompany.myspring;


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


@Controller
@RequestMapping("/")
public class rcontroller {
    @ResponseBody
    public String getFoosBySimplePath() {
    return "Get some Foos";
}


    
}

dispatch-servlet.xml：

<beans:beans xmlns="https://www.springframework.org/schema/mvc"
    xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xmlns:beans="https://www.springframework.org/schema/beans"
    xmlns:context="https://www.springframework.org/schema/context"
    xsi:schemaLocation="https://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd
        https://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans.xsd
        https://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

    <!-- DispatcherServlet Context: defines this servlet's request-processing 
        infrastructure -->

    <!-- Enables the Spring MVC @Controller programming model -->
    <annotation-driven />
    <context:component-scan base-package="com.mycompany.myspring" />

    <!-- Resolves views selected for rendering by @Controllers to .jsp resources 
        in the /WEB-INF/views directory -->
    <beans:bean>
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <beans:property name="prefix" value="/WEB-INF/" />
        <beans:property name="suffix" value=".html" />
    </beans:bean>

</beans:beans>

web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="https://java.sun.com/xml/ns/javaee" xsi:schemaLocation="https://java.sun.com/xml/ns/javaee https://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>spring-mvc-example</display-name>

    <!-- Add Spring MVC DispatcherServlet as front controller -->
    <servlet>
        <servlet-name>spring</servlet-name>
        <servlet-class>
                org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>WEB-INF/dispatch-servlet.xml</param-value>
            </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
 
    <servlet-mapping>
        <servlet-name>spring</servlet-name>
        <url-pattern>/</url-pattern> 
    </servlet-mapping>
    
 </web-app>

pom.xml：

<project xmlns="https://maven.apache.org/POM/4.0.0" xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.mycompany.myspring</groupId>
    <artifactId>SpringMVC</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>SpringMVC</name>
    <description>Spring MVC Hello World Example</description>

    <!-- Add Spring Web and MVC dependencies -->
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>4.3.9.RELEASE</version>
        </dependency>
        <!-- Servlet -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.1</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.0.0</version>
                <configuration>
                    <warSourceDirectory>WebContent</warSourceDirectory>
                </configuration>
            </plugin>
        </plugins>
        <finalName>${project.artifactId}</finalName> <!-- added to remove Version from WAR file -->
    </build>
</project>

项目结构：

Answer 1

在您的文件夹结构中，index.html 文件位于 webapp 文件夹下。但是在 dispatch-servlet.xml 文件中，您将路径设置为 WEB-INF 文件夹。

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

因此，将 index.html 文件移动到 WEB-INF 文件夹中

然后，在 web.xml 文件中配置欢迎文件，如下所示，

<display-name>spring-mvc-example</display-name>
<welcome-file-list>
    <welcome-file>index.html</welcome-file>
</welcome-file-list>

Answer 2

你的问题不是很清楚。究竟是什么问题？

反正你的dispatch-servlet.xml有问题

1- 行

 <beans:bean>
    class="org.springframework.web.servlet.view.InternalResourceViewResolver">

应该是

 <beans:bean id="viewResolver" 
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">

I.E.你不应该在类声明之前关闭标签bean，应该给它分配一个id

2- 我相信您可能对命名空间 beans: 有一些问题。如果为真，最好的想法是删除 beans: 命名空间前缀。关注这个答案

The prefix "beans" for element "beans:beans" is not bound

3- contextConfigLocation 应该是/WEB-INF/dispatch-servlet.xml

        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/dispatch-servlet.xml</param-value>

4- 在您的控制器中，您应该使用 @GetMapping 或 òRequestMapping(method=RequestMethod.GET) 映射您想要公开的方法

@GetMapping
@ResponseBody
public String getFoosBySimplePath() {

我也建议不要将控制器映射到 / 而是映射到某个子路径