Wildfly / Infinispan HTTP session replication hits ClassNotFoundException when unmarshalling CGLIB Session Bean - spring

Question

I'm running Wildfly 20.0.1.Final in standalone, two-node cluster. I'm trying to implement HTTP Session sharing between the nodes.
In my Spring web application I have <distributable/> in my web.xml.
My session object is this:
package my.package;
#Component
#Scope(value = WebApplicationContext.SCOPE_SESSION, proxyMode = ScopedProxyMode.INTERFACES)
public class MySessionBean implements Serializable {
// omitted for brevity
}
As you can see, I have ScopedProxyMode.TARGET_CLASS.
When I perform a failover in Wildfly, my HTTP Session can't be restored however, as I hit this warning:
2021-02-22 13:24:18,651 WARN [org.wildfly.clustering.web.infinispan] (default task-1) WFLYCLWEBINF0007:
Failed to activate attributes of session Pd9oI0OBiZSC9we0uXsZdBwkLnadO1l4TUfvoJZf:
org.wildfly.clustering.marshalling.spi.InvalidSerializedFormException:
java.lang.ClassNotFoundException: my.package.MySessionBean$$EnhancerBySpringCGLIB$$9c0fa1df
from [Module "deployment.myDeployment.war" from Service Module Loader]
...
Caused by: java.lang.ClassNotFoundException: my.package.MySessionBean$$EnhancerBySpringCGLIB$$9c0fa1df from [Module "deployment.myDeployment.war" from Service Module Loader]
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:255)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:410)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:398)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:116)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:398)
at org.jboss.marshalling#2.0.9.Final//org.jboss.marshalling.ModularClassResolver.resolveClass(ModularClassResolver.java:133)
at org.jboss.marshalling.river#2.0.9.Final//org.jboss.marshalling.river.RiverUnmarshaller.doReadClassDescriptor(RiverUnmarshaller.java:1033)
at org.jboss.marshalling.river#2.0.9.Final//org.jboss.marshalling.river.RiverUnmarshaller.doReadNewObject(RiverUnmarshaller.java:1366)
at org.jboss.marshalling.river#2.0.9.Final//org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:283)
at org.jboss.marshalling.river#2.0.9.Final//org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:216)
at org.jboss.marshalling#2.0.9.Final//org.jboss.marshalling.AbstractObjectInput.readObject(AbstractObjectInput.java:41)
at org.wildfly.clustering.marshalling.spi#20.0.1.Final//org.wildfly.clustering.marshalling.spi.util.MapExternalizer.readObject(MapExternalizer.java:65)
...
Note, that the ClassNotFoundException is complaining because the lack of my.package.MySessionBean$$EnhancerBySpringCGLIB$$9c0fa1df, which is the Spring-enhanced bean of my MySessionBean bean.
Changing to ScopedProxyMode.INTERFACES is not an option.
Can you please point me in the right direction with this?

Answer 1

I managed to fix this by creating a simple POJO, called MySessionDTO, and using that in my session.
So initially I had this (which threw the exception in the question):
request.getSession().setAttribute("mySession", mySessionBean);
...and after I created MySessionDTO (see below), I refactored it into this:
request.getSession().setAttribute("mySession", mySessionBean.getMySessionDTO());
MySessionDTO is a simple POJO:
package my.package;
import java.io.Serializable;
public class MySessionDTO extends MySessionBean implements Serializable {
public MySessionDTO (MySessionBean mySessionBean) {
this.setAttributeX(mySessionBean.getAttributeX());
this.setAttributeY(mySessionBean.getAttributeY());
}
}