Spring beans and dependency injection

Use standard Spring Framework techniques to define beans and inject dependencies. Constructor injection is generally recommended for wiring dependencies, while @ComponentScan locates beans. When your application class resides in a top package, @ComponentScan requires no arguments, or you may use @SpringBootApplication, which implicitly includes it. All application components, including @Component, @Service, @Repository, and @Controller, are automatically registered as Spring Beans. For beans with multiple constructors, mark the desired constructor with @Autowired. Constructor injection allows dependency fields to be marked as final, ensuring they cannot be subsequently changed after instantiation. Scope: Spring Boot. Reviewed October 4, 2026.