DelegatingSerializationFilter Could not set ObjectFilter: null warning message is repetitively appearing in console

Question

Not having any clue why is that.

Help would be appreciated. Thanks

Answer 1

Use

-Djdk.serialSetFilterAfterRead=true

See the following for more details

https://issues.redhat.com/browse/KEYCLOAK-15901

Seems like the problem is caused by ObjectInputStream.setObjectFilter (on Java 9 - 11) respective ObjectInputStream.setInternalObjectInputFilter (in Java 8) throws IllegalStateException("filter can not be set after an object has been read")