Demand origin
In the last one we have by extending access () expression of SpEL enables dynamic access control, this section will be dynamic permissions AccessDesionManager, the code is based on the "URL-based dynamic permissions: preparatory work" in the down coding.
Spring Security simple principle
Spring Security to use a large number of interceptors to intercept url, in order to manage permissions, here mainly about the two inside core processes:
(1) login authentication interceptors AuthenticationProcessingFilter.
(2) resource management interceptor AbstractSecurityInterceptor.
For achieving inside the interceptor is AuthenticationManager, accessDecisionManager other support components.