[wildfly-dev] WFLY-19020: behavior change in persistence unit handling of application client

Hi all, this question is about a change in the way that a JakartaEE application client is launched: https://issues.redhat.com/browse/WFLY-19020 Before the change, an application client might receive a ClassNotFoundException because of a missing hibernate class. My workaround for this was to add jboss-deployment-structure.xml and include the module "org.hibernate". This behavior was changed in 31.0.1 after my bugreport: it seems the application client deploys "persistence.xml" from the EJB jar somehow, and my sample now works. But this change also causes the application client to create/drop the tables each time it is launched if persistence.xml defines "hibernate.hbm2ddl.auto=create-drop". This did not happen with WildFly 31.0.0 and before. It can be avoided if the data source in "appclient.xml" points to a H2 memory database instead of the real database defined in "standalone.xml". I did not verify whether old WildFly versions required the datasource to be defined in "appclient.xml", but I have the feeling that it was necessary. Currently, this is only an unnecessary step. But if the datasource defined in "appclient.xml" would point to the "real" datasource defined in "standalone.xml", the tables would be created each time the client starts. Fortunately, I could not make it work to define a MariaDB connection in "appclient.xml" because it could not resolve the driver, but with some effort this could be possible. What do you think about this change? To me, it sounds unnecessary to create/drop tables from EJB "persistence.xml" when an app client is started. Is it required if the app client itself would use client side JPA? Best regards Wolfgang