45. Migrating from 3.x to 4.x
Upgrading from Spring Security 4.0.x is passive. These instructions are for users who are updating from Spring Security 3.2.x to 4.1.x.
As exploits against applications evolve, so must Spring Security. As a major release version, the Spring Security team took the opportunity to make some non-passive changes which focus on:
Ensuring Spring Security is more secure by default
Minimizing Information Leakage
Removing deprecated APIs
For complete details on migrating from Spring Security 3 to Spring Security 4 refer to one of the guides below: