This document discusses Spring framework concepts including autowiring, dependency injection, and bean lifecycles. It includes questions about final variables, constructor injection vs setter injection, and troubleshooting autowiring issues. The autowired annotation and how it works internally using reflection is also covered.

1. Week6. Autowired & Lifecycle
Section 7.
Covenant Ko

2. - Name. Covenant.
- Company. 11번가
- Github 용감한친구들 Organization Founder & Maintainer. https://github.com/brave-people
- Github. https://github.com/KoEonYack
- Tech Blog. https://covenant.tistory.com/ (누적 방문 41만)

3. Pop Quiz
Q. final ?

4. Pop Quiz
Q. final ?
A. (1) NPE (2) immutable

5. Pop Quiz
Q. final ?

6. Pop Quiz
Q. final ?
A. (1) (2)setter

7. Pop Quiz
Q. final ?
A. (1) (2)setter

8. Pop Quiz
Q. Constructor injection Setter injection

9. Pop Quiz Q. Constructor injection Setter injection
Setter injection should primarily only be used for optional dependencies that
can be assigned reasonable default values within the class. Otherwise, not-
null checks must be performed everywhere the code uses the dependency.
One benefit of setter injection is that setter methods make objects of that
class amenable to reconfiguration or re-injection later. Management
through JMX MBeans is therefore a compelling use case for setter injection.
Spring Docs. Core Technologies Constructor-based or setter-based DI?
https://docs.spring.io/spring-framework/docs/current/reference/html/core.html#beans-beanfactory

10. Pop Quiz Q. Constructor injection Setter injection
Setter injection should primarily only be used for optional dependencies that
can be assigned reasonable default values within the class. Otherwise, not-
null checks must be performed everywhere the code uses the dependency.
One benefit of setter injection is that setter methods make objects of that
class amenable to reconfiguration or re-injection later. Management
through JMX MBeans is therefore a compelling use case for setter injection.
Spring Docs. Core Technologies Constructor-based or setter-based DI?
https://docs.spring.io/spring-framework/docs/current/reference/html/core.html#beans-beanfactory

11. Pop Quiz Q. Constructor injection Setter injection
Setter injection should primarily only be used for optional dependencies that
can be assigned reasonable default values within the class. Otherwise, not-
null checks must be performed everywhere the code uses the dependency.
One benefit of setter injection is that setter methods make objects of that
class amenable to reconfiguration or re-injection later. Management
through JMX MBeans is therefore a compelling use case for setter injection.
Spring Docs. Core Technologies Constructor-based or setter-based DI?
https://docs.spring.io/spring-framework/docs/current/reference/html/core.html#beans-beanfactory
플랫폼 혹은 사용자에 의해 만들어진 모니터링용 객체.

12. Pop Quiz Q. Constructor injection Setter injection
https://docs.jennifersoft.com/4.5manual#21e215be955d9cbd

13. @Autowired Troubleshooting
https://page.onstove.com/soulworker/kr/view/6819574

14. @Autowired Troubleshooting
public interface {
}
@Service
public class interface {
@Autowired
;
}
@Repository
public class interface {
}
@Repository
public class interface {
}
?

15. @Autowired Troubleshooting
-
- . @Service
public class interface {
@Autowired
;
}

16. @Autowired Troubleshooting
- X
- . O @Service
public class interface {
@Autowired
;
}

17. @Autowired Troubleshooting
- X
- . O
-
-
-
@Service
public class interface {
@Autowired
;
}

18. @Autowired Troubleshooting
- X
- . O
-
- O
- X
@Service
public class interface {
@Autowired
;
}

19. @Autowired Troubleshooting
https://m.blog.naver.com/PostView.naver?isHttpsRedirect=true&blogId=pjok1122&logNo=221744930213
,
Primary

20. @Autowired Troubleshooting
https://m.blog.naver.com/PostView.naver?isHttpsRedirect=true&blogId=pjok1122&logNo=221744930213
,
Primary
Qualifier Qualifier(" ")

21. @Autowired Troubleshooting
https://m.blog.naver.com/PostView.naver?isHttpsRedirect=true&blogId=pjok1122&logNo=221744930213
,
Primary
Qualifier
Collection
Qualifier(" ")
삼성프린터, 엘지프린터, HP프린터

22. @Autowired Troubleshooting
https://m.blog.naver.com/PostView.naver?isHttpsRedirect=true&blogId=pjok1122&logNo=221744930213
Stereotype ex. @Respository(“ ”)

23. Resource - 빈 이름(id)을 통해 자동 주입(@Autowired + @Qualifier)
- 필드명과 동일한 이름의 빈을 주입
- 필드명과 빈 이름이 다르면 @Resource(name=“…”)
@Autowired Troubleshooting
Stereotype ex. @Respository(“ ”)

24. Resource - 빈 이름(id)을 통해 자동 주입(@Autowired + @Qualifier)
- 필드명과 동일한 이름의 빈을 주입
- 필드명과 빈 이름이 다르면 @Resource(name=“…”)
@Autowired Troubleshooting
Stereotype ex. @Respository(“ ”)

25. @Autowired vs @Resource
https://github.com/HwangWonGyu/news/pull/23

26. Bean Life Cycle

27. https://jakubstas.com/spring-professional-study-notes/#.YNnUJJNt9R5

28. https://jakubstas.com/spring-professional-study-notes/#.YNnUJJNt9R5
Final Bean Definition Dependency Injection

29. https://jakubstas.com/spring-professional-study-notes/#.YNnUJJNt9R5
Final Bean Definition Dependency Injection
We are here!!

31. AutowiredAnnotationBeanPostProcessor.java

32. 1. Private Reflection API
2. constructor, setter injection
3. Exception
Reflection

33. 1. Private Reflection API
2. constructor, setter injection
3. Exception
Reflection

34. PASS or FAIL
Reflection

35. - @Autowired 동작원리 (by 의뜸별)
- https://beststar-1.tistory.com/40
- @Autowired는 어떻게 동작하는 걸까?
- https://kellis.tistory.com/58
- Keesun Baik
- https://www.slideshare.net/whiteship/ss-5766801

36. Covenant Ko