Question

我正在学习Spring Boot，并且在运行应用程序时出现此错误说明：

com.example.controller.UserController中的字段userRepository需要一个无法找到的“com.example.repository.UserRepository”类型的bean。

动作：

考虑在配置中定义'com.example.repository.UserRepository'类型的bean。

所有套餐

Start.java

    package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

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

User.java

package com.example.model;

import org.springframework.data.annotation.Id;

public class User {
    @Id
    private String id;
    private String name;
    private int age;
    private String email;
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
}

UserRepository.java

    package com.example.repository;

    import org.springframework.data.mongodb.repository.MongoRepository;

    import com.example.model.User;

    public interface UserRepository extends MongoRepository<User, String>{

        public User findOneBy(String name);

    }

UserController.java

package com.example.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Repository;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.example.model.User;
import com.example.repository.UserRepository;

@Repository("com.example.repository")
@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    UserRepository userRepository;

    //Create
    @RequestMapping(method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
    public void createUser(@RequestBody User user){
        userRepository.save(user);
    }

    //Read
    @RequestMapping(value ="/{id}")
    public User readUser(@PathVariable String id){
        return userRepository.findOneBy(id);
    }

    //Update
    @RequestMapping(method = RequestMethod.PUT, consumes = MediaType.APPLICATION_JSON_VALUE)
    public void updateUser(User user){
        userRepository.save(user);
    }

    //Delete
    @RequestMapping(value ="/{id}", method = RequestMethod.DELETE)
    public void deleteUser(String id){
        userRepository.deleteById(id);
    }

}

我的日志是：

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.5.8.RELEASE)

2017-10-20 13:23:13.420  INFO 6060 --- [           main] com.example.Start                        : Starting Start on ANDRES-CASTANEDA with PID 6060 (C:\Users\andres.castaneda\Desktop\SpringBootMongoDB\SpringBootMongoDB\bin started by andres.castaneda in C:\Users\andres.castaneda\Desktop\SpringBootMongoDB\SpringBootMongoDB)
2017-10-20 13:23:13.422  INFO 6060 --- [           main] com.example.Start                        : No active profile set, falling back to default profiles: default
2017-10-20 13:23:13.471  INFO 6060 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@6b0c2d26: startup date [Fri Oct 20 13:23:13 COT 2017]; root of context hierarchy
2017-10-20 13:23:14.635  INFO 6060 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-10-20 13:23:14.647  INFO 6060 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2017-10-20 13:23:14.648  INFO 6060 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.23
2017-10-20 13:23:14.769  INFO 6060 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2017-10-20 13:23:14.769  INFO 6060 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1302 ms
2017-10-20 13:23:14.922  INFO 6060 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2017-10-20 13:23:14.925  INFO 6060 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-10-20 13:23:14.926  INFO 6060 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-10-20 13:23:14.926  INFO 6060 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-10-20 13:23:14.926  INFO 6060 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2017-10-20 13:23:14.961  WARN 6060 --- [           main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userController': Unsatisfied dependency expressed through field 'userRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.example.repository.UserRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
2017-10-20 13:23:14.963  INFO 6060 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2017-10-20 13:23:14.976  INFO 6060 --- [           main] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-10-20 13:23:15.077 ERROR 6060 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Field userRepository in com.example.controller.UserController required a bean of type 'com.example.repository.UserRepository' that could not be found.


Action:

Consider defining a bean of type 'com.example.repository.UserRepository' in your configuration.

我尝试了很多东西，但它仍然不起作用。

Answer 1

尝试将@EnableMongoRepositories添加到您的应用程序类，例如：

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@EnableMongoRepositories("com.example.repopackage")
public class Start {
    public static void main(String[] args) {
        SpringApplication.run(Start.class, args);
    }
}

只要您的MongoRepository扩展名在应用程序类包下面的包中，Spring就会自动配置它们。否则，您必须使用此批注手动指定包。

您还需要从控制器中删除@Repository注释。 @Repository只是另一个刻板印记注释，其别名为@Component。

Answer 2

可能你应该：

将所有文件移至包含Start.java的软件包（解决方案不好，但它对我有用，了解发生了什么）
使用@EnableJpaRepositories

Start.java

使用@SpringBootApplication(scanBasePackages={"com.test.pkg"})

Answer 3

您可以将模型，控制器和存储库软件包作为“ com.example”软件包的子软件包。

好像您的Start（）类找不到兄弟程序包，但可以找到子程序包。

Answer 4

这几乎不是一个解决方案，但是我在一个完整的早晨中追逐了它，最后在我的application.properties中发现了我不小心删除了MYSQL_HOST中的花括号。运行项目时，显示此线程中的错误，前面带有“ com.amazonaws.SdkClientException：无法连接到服务端点：在com.amazonaws.internal.EC2ResourceFetcher.doReadResource（...）”。因此，由于端点无法访问（在我的情况下是AWS RDS），项目开始到达异常，最终导致bean丢失。

所以我想我的意思是：检查每一步，是否遇到此错误。

Answer 5

就我而言，我已经改变了

<dependency>
        <groupId> org.springframework.data </groupId>
        <artifactId> spring-data-jpa </artifactId>
</dependency>

为

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

从maven存储库添加所需的版本（对我来说是2.4.0）

com.example.controller.UserController中的字段userRepository需要一个无法找到的类型为“com.example.repository.UserRepository”的bean

5 个答案: