Field dao in com.car.services.CarServices required a bean of type 'javax.persistence.EntityManagerFactory' that could not be found

Im trying to learn spring-boot basic application and unable to solve this error

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APPLICATION FAILED TO START

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Description:

Field dao in com.car.services.CarServices required a bean of type 'javax.persistence.EntityManagerFactory' that could not be found.

The injection point has the following annotations: - @org.springframework.beans.factory.annotation.Autowired(required=true)

Action:

Consider defining a bean of type 'javax.persistence.EntityManagerFactory' in your configuration.

repository file

@SuppressWarnings("unused")
@Transactional
@Repository
public class CarDAO implements ICarDAO {
    
    @PersistenceContext
    private EntityManager entityManager;

    @SuppressWarnings("unchecked")
    @Override
    public List<Car> getCars() {
        //String hql = "FROM Car ";
        String hql = "FROM Car as a ORDER BY a.id DESC";
        return (List<Car>) entityManager.createQuery(hql).getResultList();
    }

    @Override
    public Car getCar(int carId) {
        return entityManager.find(Car.class, carId);
    }

}

my pom.xml

<?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>2.7.8</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.car</groupId>
    <artifactId>car</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>car-demo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>javax.persistence</groupId>
            <artifactId>javax.persistence-api</artifactId>
            <version>2.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
            <version>2.7.8</version>
        </dependency>
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <version>8.0.32</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

service file

@Service
public class CarServices implements ICarServices {
    
    @Autowired
    private ICarDAO dao;

    @Override
    public List<Car> getCars() {
        return dao.getCars();
    }

    @Override
    public Car getCars(int carId) {
        return dao.getCar(carId);
    }
    

}

Controller file

@RestController
@RequestMapping("carservice")
public class CarController {
    
    
    @Autowired
    private ICarServices service;
    
    @GetMapping("car")
    public ResponseEntity<List<Car>> getCars(){
        
        List<Car> cars = service.getCars();
        return new ResponseEntity<List<Car>>(cars, HttpStatus.OK);
        
    }

}

main function

@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
public class CarDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(CarDemoApplication.class, args);
        System.out.println("hello from car");
    }

}

application.properties

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/cardb
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.tomcat.max-wait=20000
spring.datasource.tomcat.max-active=50
spring.datasource.tomcat.max-idle=20
spring.datasource.tomcat.min-idle=15

spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQLDialect
spring.jpa.properties.hibernate.id.new_generator_mappings = false
spring.jpa.properties.hibernate.format_sql = true

logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

I tried import org.springframework.beans.factory.annotation.Autowired; in my repository.java file but it didnt work for me.

You need to remove DataSourceAutoConfiguration.class from exclusions. That is what sets up the EntityManagerFactory.

So this:

@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
// Main class definition

Should be:

@SpringBootApplication()
// Main class definition