SecurityContextRepository를 사용하여 Repository 전략에 맞게 SecurityContext를 읽어오거나 초기화 기본 전략은 HttpSessionSecurityContextRepository - HttpSession을 사용한다 This filter MUST be executed BEFORE any authentication processing mechanisms. Authentication processing mechanisms (e.g. BASIC, CAS processing filters etc) expect the SecurityContextHolder to contain a valid SecurityContext by the time they execute. 기본적으로 인..