juniorSpring
What does @Autowired do?
Updated May 17, 2026
Short answer
@Autowired automatically injects dependencies into Spring beans.
Deep explanation
Spring resolves and injects matching beans by type. It can be used on constructors, setters, or fields, though constructor injection is preferred.
Real-world example
Injecting repository into service layer automatically.
Common mistakes
- Overusing field injection.
Follow-up questions
- Is @Autowired required in constructor injection?
- What if multiple beans match?