Steps to Reproduce

1. click each button, compare the final error message

Current Result

• event listener: app dev gets the original error, NullPointerException
• command method: app dev gets a wrapped java.lang.RuntimeException: doExecute comp=[<Button fJLW1>],command=[error],notifys=[[]]

Expected Result

For ZK-2638, zk should not wrap an error since it's usually an application-specific error.

if zk wraps the error, the drawbacks are:

• difficult to debug.
  because app devs always see a similar RuntimeException when executing a command, it could be an error from the service or persistence layer.
• hard to handle the error according to its type
  because all errors are RuntimeException

Debug Information

• ZK 9.6 doesn't have this bug
• caused by ZK-5048

Workaround

BinderImpl.java