session.invalidate() IllegalStateException

I'm trying to invalidate 开发者_JAVA百科a session. When I call:

session.invalidate()

it throws

java.lang.IllegalStateException: getLastAccessedTime: Session already invalidated

Any idea why? I can see the session and it's values just before the invalidate line.

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You can use an HttpSessionListener to understand where and when the Session is timing-out or getting invalidated before you call the invalidate yourself.