我的 spring 引导控制器方法出现 404 错误

Question

首先感谢帮助我。

我在调用 get 方法时遇到了这个错误，我收到 404 错误。我看到了所有文件，我认为一切正常。你能帮助我吗？我与您分享我的项目和文件的结构。

Package structure:

控制器：


import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import com.alejandrocode.demo.interfacesService.IpersonaService;
import com.alejandrocode.demo.model.Persona;

@RestController
public class Controlador {
    @Autowired
    private IpersonaService service;
    
    @GetMapping(value="/obtenerPersonas")
    public String listar(Model model) {
        List<Persona> personas = service.listar();
        model.addAttribute("personas",personas);
        return"index";
    }
}

主要class:


import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

import com.alejandrocode.demo.controller.Controlador;

@SpringBootApplication
public class ProjectAlejandroSeguridadItApplication {

    public static void main(String[] args) {
        SpringApplication.run(ProjectAlejandroSeguridadItApplication.class, args);
    }

}

界面

package com.alejandrocode.demo.interfaces;

import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

import com.alejandrocode.demo.model.Persona;

@Repository
public interface IPersona extends CrudRepository<Persona,Integer>{

}

接口服务：

package com.alejandrocode.demo.interfacesService;

import java.util.List;
import java.util.Optional;

import com.alejandrocode.demo.model.Persona;

public interface IpersonaService {
    public List<Persona> listar();
    public Optional<Persona>litarId(Integer id);
    public int save(Persona p);
    public void delete(Integer id);
}

型号

package com.alejandrocode.demo.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="persona")
public class Persona {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;
    private String name;
    private String telefono;
    private String mail;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public Persona(Integer id, String name, String telefono, String mail) {
        super();
        this.id = id;
        this.name = name;
        this.telefono = telefono;
        this.mail = mail;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getTelefono() {
        return telefono;
    }
    public void setTelefono(String telefono) {
        this.telefono = telefono;
    }
    public String getMail() {
        return mail;
    }
    public void setMail(String mail) {
        this.mail = mail;
    }
    
}

服务

package com.alejandrocode.demo.service;

import java.util.List;
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.alejandrocode.demo.interfaces.IPersona;
import com.alejandrocode.demo.interfacesService.IpersonaService;
import com.alejandrocode.demo.model.Persona;

@Service
public class PersonaService implements IpersonaService {
    @Autowired
    private IPersona data;
    @Override
    public List<Persona> listar() {
        return (List<Persona>) data.findAll();
    }

    @Override
    public Optional<Persona> litarId(Integer id) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public int save(Persona p) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public void delete(Integer id) {
        // TODO Auto-generated method stub
        
    }

}

还有我的pom.xml

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.alejandrocode</groupId>
    <artifactId>ProjectAlejandroSeguridadIT</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>ProjectAlejandroSeguridadIT</name>
    <description>Alejandro Martin Spring Boot Project</description>
    <properties>
        <java.version>16</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

我的错误：

如果您需要有关我的项目的更多信息，请告诉我回复，我会为您提供所需的一切。

非常感谢

Answer 1

第一个问题是您的包层次结构。 Spring 将无法扫描存在控制器和其他组件的其他包。

根据您的共享包层次结构，您的主要应用程序 class (ProjectAlejandroSeguridadItApplication.java) 如下包裹 package com.alejandrocode.core;

其他组件在

package com.alejandrocode.demo.*;

因此，如果您将主应用 class 移至以下包，则 spring 将能够隐式扫描和配置 bean。

package com.alejandrocode.demo;

现在您的子包将被 spring 隐式组件扫描覆盖。如果您不想移动包，那么通过在您的主应用程序中明确提到组件扫描作为 folllwing class.

来实现相同的其他方法

@ComponentScan(basePackages = "com.alejandrocode.*")
@SpringBootApplication

第二个问题是您在控制器 (Controlador.java) 中使用 @RestController 但您的主要objective 是在 thymeleaf 依赖项的帮助下使用模型数据渲染视图，因此将 @RestController 更改为 @Controller.

我的 spring 引导控制器方法出现 404 错误

404 error in my spring boot controler method

java

controller

request

maven

spring-boot