我不能@Autowired DatastoreRepository bean（Google云数据存储）

Question

我正在尝试创建 DatastoreRepository 类的 bean，但我使用

spring-boot 2.1.3

时收到以下错误

Description:

The bean 'bookRepository', defined in null, could not be registered. A bean with that name has already been defined in null and overriding is disabled.

Action:

Consider renaming one of the beans or enabling overriding by setting spring.main.allow-bean-definition-overriding=true

这是我的项目结构，我在根包中有应用程序主运行类，如下所示

com.mycompany.project    
  --Application.java
  --controller
  --domain
  --repository

带有

@SpringBootApplication

的类位于根包中

这是我的存储库类

import org.springframework.cloud.gcp.data.datastore.repository.DatastoreRepository;



public interface BookRepository extends DatastoreRepository<Book, Long>{
}

这是我的领域类

import org.springframework.cloud.gcp.data.datastore.core.mapping.Entity;
import org.springframework.data.annotation.Id;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Entity(name = "books")
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Book {
     @Id
     Long id;

     String title;
}

这是我的控制器类

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



@RestController
public class AppUserController {


    @Autowired
    BookRepository bookRepository;

    @GetMapping("/booksave")
    public String helloworld() {
        bookRepository.save(new Book(3L, "author"));

        return "book saved";
    }

}

这是我的应用程序类

@SpringBootApplication
public class Application {

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

}

Answer 1

我认为问题在于您使用注释的方式，尝试将注入更改为构造函数，例如：

@RestController
public class AppUserController {


    private BookRepository bookRepository;

    @Autowired
    public AppUserController (
            BookRepository bookRepository){
        this.bookRepository= bookRepository;
    }


    @GetMapping("/booksave")
    public String helloworld() {
        bookRepository.save(new Book(3L, "author"));

        return "book saved";
    }

}

了解它的来源：Spring @Autowire on Properties vs Constructor

Answer 2

将此注释 @EnableDatastoreRepositories 添加到您的 Application.java

Answer 3

使用Spring数据休息怎么样：

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-rest</artifactId>
    </dependency>

您无需编写控制器代码

import org.springframework.cloud.gcp.data.datastore.repository.DatastoreRepository;
import org.springframework.data.rest.core.annotation.RepositoryRestResource;


@RepositoryRestResource(collectionResourceRel = "xxxxxs", path = "xxxx")
public interface XXXXXRepository extends DatastoreRepository<XXXXX, String> 

招摇配置！！！

@Configuration
@EnableSwagger2WebMvc
@Import(SpringDataRestConfiguration.class)
public class SwaggerConfig {