Spring mvc 应用程序返回错误 (404) 未找到

Question

我是 spring 框架的新手。 我正在尝试运行简单的 spring mvc 应用程序。 据我所知，controller 具有有效路径，并且我已将所有必需的依赖项导入到项目（maven）中。 在我运行项目之前，我使用命令clean install成功运行它，但它返回HTTP 404 NOT found 错误。

这是我的项目结构。

项目结构在这里

这是配置的代码。

Here is the code Configuration.
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;



@Configuration
@EnableWebMvc
@ComponentScan(basePackages = { "net.javaguides.springmvc.form" })
public class MVCConfig implements WebMvcConfigurer{

    @Bean
    public InternalResourceViewResolver resolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setViewClass(JstlView.class);
        resolver.setPrefix("/WEB-INF/views/");
        resolver.setSuffix(".jsp");
        return resolver;
    }
    
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry
          .addResourceHandler("/resources/**")
          .addResourceLocations("/resources/"); 
    }
}

这是注册 controller controller 的代码。

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PostMapping;

import net.javaguides.springmvc.form.model.SignUpForm;

@Controller
public class SignUpController {

    /**
     * Create new signUpForm object for empty from
     * 
     * @return
     */
    @ModelAttribute("signUpForm")
    public SignUpForm setSignUpForm() {
        return new SignUpForm();
    }

    /**
     * Method to show the initial HTML form
     * 
     * @return
     */
    @GetMapping("/showSignUpForm")
    public String showForm() {
        return "signup-form";
    }

    /**
     * Save User sign up form
     * 
     * @param signUpForm
     * @param model
     * @return
     */
    @PostMapping("/saveSignUpForm")
    public String saveUser(@ModelAttribute("signUpForm") SignUpForm signUpForm, Model model) {

        // Implement business logic to save user details into a database
        // .....

        System.out.println("FirstName : " + signUpForm.getFirstName());
        System.out.println("LastName : " + signUpForm.getLastName());
        System.out.println("Username : " + signUpForm.getUserName());
        System.out.println("Password : " + signUpForm.getPassword());
        System.out.println("Email : " + signUpForm.getEmail());

        model.addAttribute("message", "User SignUp successfully.");
        model.addAttribute("user", signUpForm);

        return "signup-success";
    }

}

这是 java class 的代码。

public class SignUpForm {
    private String firstName;
    private String lastName;
    private String email;
    private String userName;
    private String password;
    public String getFirstName() {
        return firstName;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public String getLastName() {
        return lastName;
    }
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}

这是 pom.xml 的代码。

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>net.javaguides.springmvc</groupId>
  <artifactId>springmvc5-form-handling</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>springmvc5-form-handling Maven Webapp</name>
  <url>http://maven.apache.org</url>
    <properties>
        <failOnMissingWebXml>false</failOnMissingWebXml>
    </properties>
    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.0.RELEASE</version>
        </dependency>

        <!-- JSTL Dependency -->
        <dependency>
            <groupId>javax.servlet.jsp.jstl</groupId>
            <artifactId>javax.servlet.jsp.jstl-api</artifactId>
            <version>1.2.1</version>
        </dependency>
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>1.1.2</version>
        </dependency>

        <!-- Servlet Dependency -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>

        <!-- JSP Dependency -->
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>javax.servlet.jsp-api</artifactId>
            <version>2.3.1</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
    <build>
        <sourceDirectory>src/main/java</sourceDirectory>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

这是我在 tomcat 服务器上运行应用程序时的屏幕截图。

申请结果

Answer 1

在您的屏幕截图中，您正在访问一个未定义的端点。 如果访问 /showSignUpForm 或 /saveSignUpForm 时错误仍然存在，请验证 /WEB-INF/views/ 中是否存在 signup-form.jsp 和 signup-success.jsp