Improved exception handling using popup windows
If an exception occurs in the backend this exception will be thrown as an ActionExecutionException which then pops up automatically in the frontend.
When the exception occurs then the backend stops the debugging session but the frontend has no information about the backend status and possibly shows queries to be answered and the user can then still click on buttons which will cause further exceptions. Therefore it would improve the interaction to inform the frontend about the occurence of an excption and the the current state of the backend (status, query, diagnosis, testcases etc.) instead of just throwing an exception.
As a solution we could extend the DebuggingSessionStateResult with a flag class which simply contains an OK/ERROR flag and an error message to be shown with a PopUp in case the flag is set to ERROR.
The flag then has to be checked by the frontend each time and in case of the ERROR the popup window is shown and addditionally the frontend has the information of what to show in the presenters (query, diagnoses, etc).
The protocol extension is to be discussed with @bodawe