*** 中的字段存储库需要类型为 *** 的 bean，但无法找到

Question

抱歉，我是 Spring 新手， 所以我打算使用JPA连接数据库 这是我的文件夹目录： 这是

pom.xml

代码：

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.3</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>CoursearnsSpring</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</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-webflux</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.session</groupId>
            <artifactId>spring-session-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.thymeleaf.extras</groupId>
            <artifactId>thymeleaf-extras-springsecurity6</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>io.projectreactor</groupId>
            <artifactId>reactor-test</artifactId>
            <scope>test</scope>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-test</artifactId>
            <scope>test</scope>
        </dependency>
        
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <type>jar</type>
        </dependency>
        
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <type>jar</type>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>

        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
            <scope>runtime</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

运行文件：

@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
@ComponentScan(basePackages = "com.example.CoursearnsSpring.repository")
public class DemoApplication implements CommandLineRunner{
    @Autowired
    private CourseRepository repository; 
    
    public static void main(String[] args)  {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        System.out.println(repository.findAll());
    }
}

和存储库

@Repository
public interface CourseRepository extends JpaRepository<Course, Long> {
}

模型.课程：

@Entity
@Table(name = "Course")
public class Course {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    Long id;

    String name;
    String description;
    String teacher_id;//the creators
    String admin_id;//the approvals
    String header;
    String tags;
    String displayname;//name of said user

应用程序属性：

spring.datasource.url=jdbc:sqlserver://localhost\\SQLEXPRESS:1433;databaseName=Coursearn
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql = true
spring.jpa.hibernate.ddl-auto = update

当我尝试运行时，总是出现错误：

Field repository in com.example.CoursearnsSpring.DemoApplication required a bean of type 'com.example.CoursearnsSpring.repository.CourseRepository' that could not be found.

即使我使用

@ComponentScan(basePackages = "com.example.CoursearnsSpring.repository")

来确保它可以扫描正确的目录，但仍然出现相同的错误

Answer 1

好吧，我 2 小时后回来了，我不知道为什么我会再遇到这个错误，但我知道如何修复，这样像我这样卡在这里的人可能会看到代码行中的谎言比它本来的样子更漂亮 （所有这些都是在application.properties中完成的）

• 1, 在sql上添加加密/信任证书
• 2,添加SQL驱动
• 3、添加SQL方言2012
• 4、这些东西也可能导致找不到bean的错误，所以不要惊慌，把所有东西都重新整理一下