ValidationException: the interface does not define a valid remote business interface; the method does not conform to RMI rules

Question

I got the following exception on IBM WebSphere Application Server when starting my EJB application:

com.ibm.wsspi.amm.validate.ValidationException: the interface YourInterface does not define a valid remote business interface; the method yourMethod does not conform to RMI rules

I checked Oracle's documentation for the RMI confirmity rules, but that didn't help. I also found a problem ticket from IBM describing exactly my problem, but giving an obscure solution by setting an undocumented JVM property - this didn't work either.

Answer 1

The problem was that one of my method's parameters didn't implement java.io.Serializable.

So to tackle this rather generic error, you should check all your parameters that they implement this interface.