bug: NullPointerException

[cmgyqjj]

Bug describion
In the case of login failure, such as when the user ID is not registered, the offLine method will be called upon exiting the client. Within this method, an attempt is made to retrieve the login flag based on the UserId. However, since the login has already failed, the operation to obtain the flag will result in a NullPointerException (NPE).

Can I submit a Pull Request (PR) to add an online check in the logout process to prevent a NullPointerException (NPE)?

Reproduction
Reproduction Steps:

1. Start the server and route services.
2. Launch the client service with an unregistered ID and attempt to log in.
3. Exit the client service.

Expected results
If the user is not logged in, the current user logout process will be skipped directly.

screenshot