无法在Spring Boot中自动加载@Repository注释接口

Question

我正在开发一个spring boot应用程序,我在这里遇到了一个问题.我正在尝试注入一个@Repository注释接口,它似乎根本不起作用.我收到了这个错误

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'springBootRunner': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.pharmacy.persistence.users.dao.UserEntityDao com.pharmacy.config.SpringBootRunner.userEntityDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.pharmacy.persistence.users.dao.UserEntityDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:957)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:946)
    at com.pharmacy.config.SpringBootRunner.main(SpringBootRunner.java:25)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.pharmacy.persistence.users.dao.UserEntityDao com.pharmacy.config.SpringBootRunner.userEntityDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.pharmacy.persistence.users.dao.UserEntityDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
    ... 16 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.pharmacy.persistence.users.dao.UserEntityDao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1301)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1047)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
    ... 18 common frames omitted

这是我的代码:

主要应用类:

package com.pharmacy.config;

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


@SpringBootApplication
@ComponentScan("org.pharmacy")
public class SpringBootRunner {


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

实体类:

package com.pharmacy.persistence.users;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;



@Entity
public class UserEntity {

    @Id
    @GeneratedValue
    private Long id;
    @Column
    private String name;

}

存储库界面:

package com.pharmacy.persistence.users.dao;

import com.pharmacy.persistence.users.UserEntity;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;


@Repository
public interface UserEntityDao extends CrudRepository<UserEntity,Long>{

}

控制器:

package com.pharmacy.controllers;

import com.pharmacy.persistence.users.UserEntity;
import com.pharmacy.persistence.users.dao.UserEntityDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;


@RestController
public class HomeController {


    @Autowired
    UserEntityDao userEntityDao;

    @RequestMapping(value = "/")
    public String hello() {
        userEntityDao.save(new UserEntity("ac"));
        return "Test";

    }
}

的build.gradle

buildscript {
    ext {
        springBootVersion = '1.2.2.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'idea'
apply plugin: 'spring-boot'
mainClassName = "com.pharmacy.config.SpringBootRunner"
jar {
    baseName = 'demo'
    version = '0.0.1-SNAPSHOT'
}


repositories {
    mavenCentral()
}


dependencies {
    compile("org.springframework.boot:spring-boot-starter-data-jpa")
    compile("org.springframework.boot:spring-boot-starter-web")
    compile("org.springframework.boot:spring-boot-starter-ws")
    compile("postgresql:postgresql:9.0-801.jdbc4")

    testCompile("org.springframework.boot:spring-boot-starter-test")
}

application.properties:

spring.view.prefix: /
spring.view.suffix: .html

spring.jpa.database=POSTGRESQL
spring.jpa.show-sql=false
spring.jpa.hibernate.ddl-auto=update


spring.datasource.driverClassName=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/postgres
spring.datasource.username=postgres
spring.datasource.password=abc123

我甚至将我的代码与访问数据jpa进行了比较,并且我已经没有想法这个代码有什么问题了.任何帮助赞赏.提前致谢.

编辑:我改变了我的代码,如上所示,当我将我的@Repository接口注入另一个组件时,我没有收到该错误.但是,我现在遇到了一个问题 - 我的组件无法检索(我使用过调试).我做错了所以春天找不到我的组件？

Answer 1

当存储库包与@SpringBootApplication/不同时@EnableAutoConfiguration,@EnableJpaRepositories需要明确定义基本包.

尝试添加@EnableJpaRepositories("com.pharmacy.persistence.users.dao")到SpringBootRunner

Answer 2

我没有找到存储库时遇到同样的问题.所以我所做的就是将所有内容都移到一个包中.这意味着我的代码没有任何问题.我将Repos和Entities移动到另一个包中,并将以下内容添加到SpringApplication类中.

@EnableJpaRepositories("com...jpa")
@EntityScan("com...jpa")

之后,我将Service(接口和实现)移动到另一个包,并将以下内容添加到SpringApplication类中.

@ComponentScan("com...service")

这解决了我的问题.

Answer 3

我想分享这类问题还有另外一个原因,因为我在这个问题上挣扎了一段时间,我找不到任何答案.

在像以下的存储库中:

@Repository
public interface UserEntityDao extends CrudRepository<UserEntity, Long>{

}

如果实体UserEntity 不具有的@Entity对类注释,你会有同样的错误.

这种错误令人困惑,因为您专注于尝试解决有关Spring未找到存储库但问题是实体的问题.如果您在尝试测试存储库时得到了这个答案,这个答案可能会对您有所帮助.

Answer 4

看来您的@ComponentScan注释设置不正确.试试:

@ComponentScan(basePackages = {"com.pharmacy"})

实际上,如果您的主类位于结构的顶部,例如直接在com.pharmacy包下,则不需要组件扫描.

此外,您不需要两者

@SpringBootApplication
@EnableAutoConfiguration

该@SpringBootApplication注释包括@EnableAutoConfiguration默认.

Answer 5

我有一个类似的问题,我NoSuchBeanDefinitionException在Spring Boot 中接收(基本上在处理CRUD存储库时),我不得不在主类上添加以下注释:

@SpringBootApplication   
@EnableAutoConfiguration
@ComponentScan(basePackages={"<base package name>"})
@EnableJpaRepositories(basePackages="<repository package name>")
@EnableTransactionManagement
@EntityScan(basePackages="<entity package name>")

此外,请确保@Component在实现上具有注释.

Answer 6

在 SpringBoot 中，默认情况下不会自动启用 JpaRepository。您必须明确添加

@EnableJpaRepositories("packages")
@EntityScan("packages")

Answer 7

@SpringBootApplication(scanBasePackages=,<youur package name>)
@EnableJpaRepositories(<you jpa repo package>)
@EntityScan(<your entity package>)

Entity class like below 
@Entity
@Table(name="USER")
public class User {

    @Id
    @GeneratedValue

Answer 8

为了扩展上述答案，您实际上可以在 EnableJPARepositories 标记中添加多个包，这样您在仅指定存储库包后就不会遇到“对象未映射”错误。

@SpringBootApplication
@EnableJpaRepositories(basePackages = {"com.test.model", "com.test.repository"})
public class SpringBootApplication{

}