Spring Boot：考虑在配置中定义一个名为“entityManagerFactory”的bean

Question

尝试启动Spring Boot应用程序时，我收到以下错误：

注意：仅当我将自动连线注释置于IDeviceRepository IDeviceRepository上方时，才会发生此错误 。java类

我还没有让DeviceDao.java持久化到数据库-但是正在创建实体

> *************************** 
> APPLICATION FAILED TO START
> ***************************
> 
> Description: 
> Field iDeviceRepository in com.abc.dao.DeviceDao required a bean named 'entityManagerFactory' that could not be found. 
> Action:
> Consider defining a bean named 'entityManagerFactory' in your configuration.

这是项目的目录结构：

├───src
│   ├───main
│   │   ├───java
│   │   │   └───com
│   │   │       └───abc
│   │   │           ├───controller
│   │   │           ├───dao
│   │   │           │   └───repositories
│   │   │           ├───init
│   │   │           ├───model
│   │   │           ├───service
│   │   │           └───util
│   │   │               ├───common
│   │   │               ├───enums
│   │   │               ├───exceptions
│   │   │               └───interfaces
│   │   └───resources
│   │       ├───static
│   │       │   ├───css
│   │       │   ├───fonts
│   │       │   ├───img
│   │       │   └───js
│   │       └───templates

com。美国广播公司。初始化。应用JAVA

package com.abc.init;

@SpringBootApplication
@EnableJpaRepositories("com.abc.dao.repositories")
@EntityScan(basePackages = { "com.abc.model" })
@ComponentScan(basePackages={ "com.abc.controller", "com.abc.service", "com.abc.dao" })
public class Application
{
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

com.abc.controller.ontroller.java

package com.abc.controller;

@Controller
public class RegisterController
{
    @Autowired
    RegisterServiceImpl registerService;

    @GetMapping("/register")
    public String registerForm(Model model) {
        model.addAttribute("device", new Device());
        return "registerDevice";
    }

    @PostMapping("/register")
    public String registerSubmit(@ModelAttribute Device device) {
        registerService.registerDevice(device)
        return "registerDeviceSuccess";
    }
}

com。美国广播公司。服务RegisterServiceImpl。JAVA

package com.abc.service;

@Service
public class RegisterServiceImpl implements IRegisterService
{
    @Autowired
    DeviceDao devDao;

    public boolean registerDevice (Device device) {
        devDao.saveDevice(device);
        return true;
    }
}

com.abc.util.interfaces.注册服务

package com.abc.util.interfaces;

public interface IRegisterService
{
    public boolean registerDevice(Device device);
}

com。美国广播公司。道。设备DAO。JAVA

package com.abc.dao;

@Repository
public class DeviceDao 
{
    @Autowired
    IDeviceRepository iDeviceRepository;

    public Device saveDevice(Device device) {
        return iDeviceRepository.save(device);
    }
}

com.abc.dao.repositories.IDeviceRepository.java

package com.abc.dao.repositories;

@Repository
public interface IDeviceRepository extends CrudRepository<Device, Long> {}

application.properties

# Exposed HTTP Port
server.port = 8090

# Database Configuration Parameters
spring.datasource.url=jdbc:postgresql://localhost:5432/mydb
spring.datasource.username=mydbadmin
spring.datasource.password=mydbpassword
spring.datasource.driver-class-name=org.postgresql.Driver

# Hibernate Configurations
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false

# Display SQL Commands in Terminal
spring.jpa.show-sql=true

堆栈跟踪：

java.lang.IllegalStateException: Failed to load ApplicationContext
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registerController': Unsatisfied dependency expressed through field 'registerService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registerServiceImpl': Unsatisfied dependency expressed through field 'devDao'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'deviceDao': Unsatisfied dependency expressed through field 'iDeviceRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'IDeviceRepository': Cannot create inner bean '(inner bean)#36dce7ed' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#36dce7ed': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registerServiceImpl': Unsatisfied dependency expressed through field 'devDao'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'deviceDao': Unsatisfied dependency expressed through field 'iDeviceRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'IDeviceRepository': Cannot create inner bean '(inner bean)#36dce7ed' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#36dce7ed': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'deviceDao': Unsatisfied dependency expressed through field 'iDeviceRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'IDeviceRepository': Cannot create inner bean '(inner bean)#36dce7ed' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#36dce7ed': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'IDeviceRepository': Cannot create inner bean '(inner bean)#36dce7ed' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#36dce7ed': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#36dce7ed': Cannot resolve reference to bean 'entityManagerFactory' while setting constructor argument; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available

有人能指点一下吗？

Answer 1

几个月前，当我开始学习Spring Boot时，我也遇到了类似的问题。我不确定Spring是否认真对待目录结构。我的目录结构与@Pawan相似。您所要做的就是将存储库文件夹向上移动一级，即将其移动到父abc文件夹中。用@服务为DeviceDao类添加注释。最后在@EnableJpaRepository中更新存储库路径。这对我有用。希望这有帮助。

Answer 2

在spring boot中，您不需要使用repository注释来注释repository类。

@Repository

您只需要在接口上扩展JPARepository，剩下的就由Spring boot来处理了。例如：

public interface YourRepository extends JpaRepository<YourDomain, Serializable> {

    YourDomain findBysomeparameter(Long parameter);

}

您不需要添加这些注释：

@EnableJpaRepositories
@EntityScan
@ComponentScan

除非您正在进行一些配置，否则Spring boot会自动执行此操作。

我希望这会有所帮助。