Mis vahe on Filters, Interceptors ja Listeners Springis?

• Filters (Spring Web): Intercept requests and responses at the servlet level. Used for modifying requests/responses, authentication, authorization, logging before the request reaches the controller. Applied to URL patterns.

• Interceptors (Spring MVC): Intercept requests at the Spring MVC level. Work after Filters, but before the request is handled by the controller. Allow actions before (preHandle), after (postHandle), and after completion (afterCompletion). Used for model manipulation, access control at the controller level. Applied to controller methods.

• Listeners (Spring Context): React to events in the Spring context. Allow actions on startup or shutdown of the context, upon receiving specific event types. Used for resource initialization, data cleanup, or executing tasks when application state changes. Operate independently of web requests. Implement the ApplicationListener interface.

Here is a comparative table:

Feature	Filters	Interceptors	Listeners
Level	Servlet	Spring MVC	Spring Context
When it works	Before and after servlet	Before, after controller and completion	When an event occurs
Applies to	URL patterns	Controller methods	Event types
Purpose	Modifying request/response, authentication	Manipulating model, authorization at controller level	Reacting to context events
Interface	javax.servlet.Filter	org.springframework.web.servlet.HandlerInterceptor	org.springframework.context.ApplicationListener