org.sf.beans.factory.NoSuchBeanDefinitionException: 没有可用的类型 X 的合格 bean

Question

我正在尝试使用 Spring 中的用户存储库设置一个简单的项目 Spring 使用 Hibernate 作为 JPA 启动，我尝试 this and this tutorials and in both (and everywhere) @SpringBootApplication seems to be sufficient to make the repository reachable throughout the app's scope since it includes @ComponentScan, except, in my case, it is not. Even 看起来适合我的情况，但是没有。

项目结构

project
│   └── src
│       └── main
│           └── java
│               └── medisam
|                    └── Application.java
│   └── src
│       └── main
│           └── java
│               └── medisam
│                   └── entity
│                       └── User.java
|                       └── UserRepository.java
│    └── src
│        └── main
│            └── java
│               └── medisam
│                   └── controller
│                       └── MainController.java

具有这样的结构和代码：

@SpringBootApplication
public class Application {
    ...
    private static final Logger LOG = LoggerFactory.getLogger(Application.class);
    @Autowired
    private UserRepository repo;

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

我得到：

...创建名称为 的 bean 时出错 'application' ：未满足的依赖通过字段'repo'表示；嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有符合条件的bean类型'medisam.entity.UserRepository' 可用：预计至少有 1 个 bean 符合 autowire 候选人。依赖注解： {@org.springframework.beans.factory.annotation.Autowired(required=true)} ...

只有当我这样做的时候:

@ComponentScan(basePackages = {"medisam.controller", "medisam.entity"})
@EntityScan({"medisam.entity"})
@EnableJpaRepositories(basePackages = {"medisam.entity"})
public class Application {
    ...
    private static final Logger LOG = LoggerFactory.getLogger(Application.class);
    @Autowired
    private UserRepository repo;

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

我得到了一个工作代码，但是，如果真的有一种只用 @SpringBootApplication 就可以实现的方法，我想使用它。

难道是@SpringBootApplication没有扫描正确？

请帮忙

编辑

UserRepository.java

package medisam.entity;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface UserRepository extends JpaRepository<User, Integer> {

}

User.java

package medisam.entity;

import java.util.Set;
import javax.persistence.Access;
import javax.persistence.AccessType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;

@Entity
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    private String name;
    private String email;
    private String username;
    private String password;
    private boolean enabled;

    @ManyToMany(targetEntity = Role.class)
    @Access(AccessType.FIELD)
    @JoinTable(name = "user_role", joinColumns = @JoinColumn(name = "user_id", referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "role_id", referencedColumnName = "id"))
    private Set<Role> roles;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    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;
    }

    public boolean isEnabled() {
        return enabled;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public Set<Role> getRoles() {
        return roles;
    }

    public void setRoles(Set<Role> roles) {
        this.roles = roles;
    }
}

Answer 1

我在 gihub 上查看了您的代码，发现您在 class Application.java 和 ServiceResponse.java.

中导入了错误的包名称

请将主包导入为 package medisam; 而不是 package hello;。

如下所示：

您的申请class:

package medisam;
import medisam.entity.UserRepository;
import nz.net.ultraq.thymeleaf.LayoutDialect;
import nz.net.ultraq.thymeleaf.decorators.strategies.GroupingStrategy;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Description;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;
import org.thymeleaf.extras.java8time.dialect.Java8TimeDialect;
import org.thymeleaf.extras.springsecurity4.dialect.SpringSecurityDialect;
import org.thymeleaf.spring5.SpringTemplateEngine;
import org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver;
import org.thymeleaf.spring5.view.ThymeleafViewResolver;
import org.thymeleaf.templatemode.TemplateMode;
import org.thymeleaf.templateresolver.ITemplateResolver;
import org.thymeleaf.templateresolver.UrlTemplateResolver;

@SpringBootApplication
public class Application {

这是您的服务响应

package medisam;

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import org.apache.catalina.util.ResourceSet;

import java.util.ArrayList;
import java.util.List;

@JsonIgnoreProperties(ignoreUnknown = true)
public class ServiceResponse {

org.sf.beans.factory.NoSuchBeanDefinitionException: 没有可用的类型 X 的合格 bean

org.sf.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type X available

java

hibernate

repository

spring-boot

component-scan