java - “Could not autowire. No beans of type… found”与简单项目

我下载了简单的JPA Spring Boot tutorial，效果很好。但是，当我尝试在自己的测试项目中复制这种简单行为时，在返回CommandLineRunner的Application.demo()方法中的bean注入(inject)中遇到“无法 Autowiring ”错误。这个项目太准了，我什至都不知道要提交什么，但这是POM:

<?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.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

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

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.1.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-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </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>

和应用程序。

package com.example;

@SpringBootApplication
public class TestApplication {

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

    @Bean
    //errors with: "Could not autowire. No beans of 'SimpRepository' type found"
    public CommandLineRunner demo(SimpRepository repository) {
        return (args) -> {

        };
    }
}

和存储库服务:

package com.example;
public interface SimpRepository extends CrudRepository<Simp, Long> {

}

对于以下实体:

package com.example;
@Entity
public class Simp {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    private String value;

    public Simp(String value) {
        this.value = value;
    }
}

最佳答案

这里有两种可能。

您需要将@EnableJpaRepositories(basePackages = {"your.pkg.here"})添加到TestApplication中。这告诉Spring Data在指定的包下查找您的存储库类。如果存储库软件包名称与TestApplication相同，则可以跳过basePackages部分。

同样，如果您的TestApplication和SimpRepository不在同一软件包中，则需要在所有相关软件包的列表中添加@ComponentScan。