There are a few common reasons that logging in with the same user does not trigger a logout event. The first occurs when using custom UserDetails (as we did in Chapter 3, Custom Authentication) while the equals and hashCode methods are not properly implemented. This occurs because the default SessionRegistry implementation uses an in-memory map to store UserDetails. In order to resolve this, you must ensure that you have properly implemented the hashCode and equals methods.
The second problem occurs when restarting the application container while the user sessions are persisted to a disk. When the container has started back up, the users who were already logged in with a valid session are logged in. However, the in-memory map of SessionRegistry that is used to determine if the user is already logged in will be empty. This means that Spring...
