beginnerSpring Security Architecture: The Filter Chain & Internal Flow

Why does Spring Security use an AnonymousAuthenticationToken instead of leaving Authentication null?

Using a real (but low-privilege) Authentication object for unauthenticated users lets the rest of the framework (authorization checks, method security, logging) treat every request uniformly without constant null-checks — an anonymous user is just a principal with an authority like ROLE_ANONYMOUS rather than a special null case.

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