Update example: @PreAuthorize and @Async don't play together out of the box

[peholmst]

Page: https://vaadin.com/docs/latest/building-apps/application-layer/background-jobs/triggers

There is an example that combines @PreAuthorize and @Async. However, this will not work out of the box since the security check is performed after the background thread has started to execute the job.

You need to use a DelegatingSecurityContextAsyncTaskExecutor for the security check to work. Note that any access denied exceptions are caught by the background thread and not the calling thread.

It may be easier to just use programmatic task execution when also dealing with security.