How are Interceptors and Servlet Filters different?

Answer

1. Filters are part of the Servlet API, Interceptors are Struts 2.
2. The Interceptor stack fires on requests in a configured package while filters only apply to their mapped URLs.
3. Interceptors can be configured to execute or not depending on specific target action methods via excludeMethods and includeMethods while Filters lack this feature.
4. Filters are an implementation of the Intercepting Filter pattern while Interceptors are of the Interceptor pattern.