The top lines of the stack trace point to UserForm.java line 109 and 119, so maybe you can apply a null check somewhere there
yes, its ok as workaround. but the problem is why i have changeEvent before selecting row.
anyway i think this topic can be closed. TY a lot for help!
Just a tip: I would probably not have a Spring (core) dependency specified in the pom. Spring Boot has a Spring dependency and will pull the correct version transitively. I would rather Spring Boot (and the team behind) solve the dependency than trying to do this manually. The versions do however match so that is not an issue this time at least.