The difference between <context:annotation-config> and <context:component-scan> in Spring MVC revolves primarily around their roles in bean registration and annotation processing within the Spring container.
<context:annotation-config>
The <context:annotation-config> tag is used specifically to activate annotations on beans that have already been registered in the Spring application context. This tag does not itself register any beans; instead, it is used to enhance beans that are already managed by the Spring container. It processes annotations like @Autowired, @Resource, @PostConstruct, @PreDestroy, and @Required on existing beans, regardless of how these beans were registered (either through XML configuration or through component scanning)[2][3].
<context:component-scan>
On the other hand, <context:component-scan> is a more comprehensive directive that not only activates annotations but also automatically detects and registers bean definitions. When you use <context:component-scan>, Spring scans the specified packages and automatically registers beans for any classes annotated with stereotype annotations such as @Component, @Service, @Repository, @Controller, etc. This tag effectively subsumes the functionality of <context:annotation-config> because it not only detects and registers beans but also activates annotations on them[2][3][5].
Key Differences
Bean Registration: <context:component-scan> registers beans automatically from the specified packages based on annotations, whereas <context:annotation-config> only processes annotations on already registered beans.
Scope of Functionality: <context:component-scan> includes the functionality of <context:annotation-config> (activat...
