public void invalidateSession(String identifier) {

        // Do not attempt to remove a null identifier
        if (identifier == null)
            return;

        // Remove from the overall list of sessions
        sessions.remove(identifier);

        // Remove from the set of pending sessions
        pendingSessions.remove(identifier);

    }
Remove the session associated with the given identifier, if any, from the
map of sessions, and the set of pending sessions.

@param identifier
    The identifier of the session to remove, if one exists.
guacamole-ext/src/main/java/org/apache/guacamole/net/auth/AuthenticationSessionManager.java