How to do something after the login with Spring Security?

I have a Spring web application which uses Spring SAML and Spring Security to manage the login process. Now I need to do some tasks after the correct login occurs. In particular I have to store some data in the SecurityContext.getContext() object.

I have never worked with Spring Security/SAML and I don't know how it manages the return from the IdP.

Is there any place in the code where usually you can put your code after the login process ends correctly?

I mean, I know where the redirect page is set but I cannot put my custom code in the Controller of this redirect page because that page is accessed more than one time, and I need to run my custom code only once at login time.