Spring initialization done outside the project - spring

Question

I have a java spring project . I see that one way of initialing the spring project is using this code in the main method.
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
ctx.register(Config.class);
ctx.scan("com.example.db.app");
ctx.refresh();
Is it possible to keep this outside a main method and then make a jar of this project. Add it as a dependency in pom.xml in other project and call the method which initializes the spring artifacts from there.
I tried doing it. I am getting an error.
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'itemInformationRepositoryService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire method: public void com.example.db.app.service.ItemInformationRepositoryService.setItemInformationRepositoryService(com.example.db.app.repository.ItemInformationRepository); nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.example.db.app.repository.ItemInformationRepository] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}

Answer 1

The exception message states:
No qualifying bean of type [com.example.db.app.repository.ItemInformationRepository] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency.
This means that the class com.example.db.app.repository.ItemInformationRepository is not in the Spring context. Perhaps you were expecting Spring to discover this class as a result of your instruction to Spring to scan com.example.db.app? According to the Javadocs for AnnotationConfigApplicationContext.scan() ...
Perform a scan within the specified base packages.
#param basePackages the packages to check for annotated classes
So, in order for Spring to discover com.example.db.app.repository.ItemInformationRepository you must either:
Annotate it with org.springframework.stereotype.Component so that it is discovered by scan()
Register it in the same way as you are registering Config.class e.g. ctx.register(ItemInformationRepository.class);