找不到MongoRepository的bean（Spring Boot）

Question

我正在使用Spring Boot和MongoDB。

Spring version : 4.3.9

Spring boot version : 1.5.4

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

@Repository
public interface HotelRepository extends MongoRepository<Hotel,String> {
}

但是，每当我向HotelRepository添加依赖项时，编译器会在com.demo.hotelController中给出错误字段HotelRepository时，就需要一个类型为“com.demo.HotelRepository”的bean，但无法找到该bean。

@RestController
@RequestMapping("/hotel")
public class HotelController {

    @Autowired
    private HotelRepository hotelRepository;

    @GetMapping("/all")
    public List<Hotel> getAllHotels(){
        return this.hotelRepository.findAll();
    }
}

为了解决这个错误，我从我的角度检查了所有方面，但都是徒劳的。我研发的东西。

• 对于hotelrepository将提供一个现成的默认实现。根据Spring文档
• 我已经用@repository注释了接口，因此不需要将@component
• 使用@autowired注释从spring上下文添加依赖项，因此它应该从spring上下文中选择已创建的bean。
• 所有必需的文件都在同一个包中，因此不需要将@componentscan

下面是我的主要spring boot应用程序类：

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

@SpringBootApplication
public class MongoWithBootApplication {

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

应用程序.属性：

spring.data.mongodb.host=localhost
spring.data.mongodb.port=27017
spring.data.mongodb.database=HotelDB

堆栈跟踪：

2017-07-10 13:25:12.485  INFO 4712 --- [           main] com.demo.MongoWithBootApplication        : Starting MongoWithBootApplication on KELLGGNCPU0313 with PID 4712 (D:\STS_WS\MongoWithBoot\target\classes started by mehrajuddin.malik in D:\STS_WS\MongoWithBoot)
2017-07-10 13:25:12.487  INFO 4712 --- [           main] com.demo.MongoWithBootApplication        : No active profile set, falling back to default profiles: default
2017-07-10 13:25:12.519  INFO 4712 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@13acb0d1: startup date [Mon Jul 10 13:25:12 IST 2017]; root of context hierarchy
2017-07-10 13:25:13.448  INFO 4712 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-07-10 13:25:13.456  INFO 4712 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2017-07-10 13:25:13.456  INFO 4712 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.15
2017-07-10 13:25:13.541  INFO 4712 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2017-07-10 13:25:13.541  INFO 4712 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1025 ms
2017-07-10 13:25:13.635  INFO 4712 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2017-07-10 13:25:13.637  INFO 4712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-07-10 13:25:13.638  INFO 4712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-07-10 13:25:13.638  INFO 4712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-07-10 13:25:13.638  INFO 4712 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2017-07-10 13:25:13.673  WARN 4712 --- [           main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'hotelController': Unsatisfied dependency expressed through field 'hotelRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.demo.HotelRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
2017-07-10 13:25:13.675  INFO 4712 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2017-07-10 13:25:13.684  INFO 4712 --- [           main] utoConfigurationReportLoggingInitializer : 

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-07-10 13:25:13.737 ERROR 4712 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

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

Description:

Field hotelRepository in com.demo.HotelController required a bean of type 'com.demo.HotelRepository' that could not be found.


Action:

Consider defining a bean of type 'com.demo.HotelRepository' in your configuration.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.demo</groupId>
    <artifactId>MongoWithBoot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>MongoWithBoot</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

Answer 1

面对类似的问题，在Application类中添加以下内容帮助我解决了这个问题

@EnableMongoRepositories(basePackageClasses = DeviceDataRepository.class)

在你的情况下

@SpringBootApplication
@EnableMongoRepositories(basePackageClasses = HotelRepository.class)
public class MongoWithBootApplication{ ... }