Spring boot cannot find beans - spring-boot

Question

i have a Spring Boot project which has some external packages i need to import as Beans in the main application.
So i have my main application in com.package.app package and some classes (among which some repositories) in com.package.commons package.
In order to take these beans i have my main class annotated as follows:
#SpringBootApplication
#ComponentScan({ "com.package.commons" ,"com.package.app"})
#EnableScheduling
#EnableAsync
public class EmanagerApplication extends SpringBootServletInitializer{
public static void main(String[] args) {
SpringApplication.run(EmanagerApplication.class, args);
}
}
But when i launch the application it may occur (not always but very ofter) that the start up fails with these kind of error:
Description:
Field repository in com.package.commons.service.BrandService required a bean of type 'com.package.commons.persistence.repository.BrandRepository' that could not be found.
Action:
Consider defining a bean of type 'com.package.commons.persistence.repository.BrandRepository' in your configuration.
My BrandRepository is annotated with #Repository and the service class with #Service
The really strange thing is that if i keep launching the app at the end it stars... but there is no reason for it...

Answer 1

If you're using JPA, you'll also need the #EnableJpaRepositories annotation.
Also consider to use #EnableTransactionManagement to enable declarative transaction handling.
E.g. use something like the following in the same package or a parent package where you have your JPA entities and JPA repositories (untested):
import java.util.HashMap;
import java.util.Map;
import javax.sql.DataSource;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.boot.autoconfigure.orm.jpa.JpaBaseConfiguration;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.boot.autoconfigure.transaction.TransactionManagerCustomizers;
import org.springframework.orm.jpa.vendor.AbstractJpaVendorAdapter;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.jta.JtaTransactionManager;
#Configuration
#EntityScan
#EnableJpaRepositories
#EnableTransactionManagement
public class HibernateConfig extends JpaBaseConfiguration {
public HibernateConfig(DataSource dataSource, JpaProperties properties, ObjectProvider<JtaTransactionManager> jtaTransactionManager,
ObjectProvider<TransactionManagerCustomizers> transactionManagerCustomizers) {
super(dataSource, properties, jtaTransactionManager, transactionManagerCustomizers);
}
#Override
protected AbstractJpaVendorAdapter createJpaVendorAdapter() {
return new HibernateJpaVendorAdapter();
}
#Override
protected Map<String, Object> getVendorProperties() {
return new HashMap<>();
}
}
And don't forget to annotate your #Service classes also with #Transactional.

Answer 2

If you confirm that the Application which with the startup method of this application is good, and confirm the #ComponentScan is good also. And the configuration file yaml or properties of JPA also good.
How about trying extends JPA Repository like this:
public class xxxResponsitory extends JpaRepository<T, E>{
...
}
Cause JpaRepository has already annotated with #Repository annotation, T means the type of Primary Key, I always use Integer or Long, autoboxing type. E means the main type of this repository.
Make an example:
Now we have an Entity type named User, the Primary key type of User is Long, I would write the repository like this:
public class UserRepository extends JpaRepository<Long, User>{
...
}
Don't need annotated anything, then, In the service class, #Autowried UserRepository, everything is good to run. But make sure the things that I talk at the start of my answer.
Hope this can help you.