check http://forum.springsource.org/showthread.php?27846-Spring-is-non-invasive
What does it really means?
"You are not forced to import or extend any Spring APIs, example Struts forces you to extend Action".
Of course in some areas, such as the web framework, it's impossible to avoid aplication code depending on the framework. But Spring consistently attempts to reach the non-invasive ideal where configuration management is concerned
