Transform objects on (de)serialization

Question

Hi,
I would like to know if it is possible in principle to transform/mutate/repack an object to another object such that it belongs to a different class.
Scenario: I want to pass a list of groovy objects POGOs to an applet. These groovy objects however have groovy.lang.GroovyObject as its root parent and not java.lang.Object. I don't want to have the applet load the whole groovy runtime and I want to avoid an extra repack step. So the idea is that the serialization (writeObject(), readObject()) does the magic of transforming the POGOs (Groovy) to POJOs (Java). Is that possible or are there some fundamental barriers?
Thanks
fatzopilot

Answer 1

Hi ejp,
thanks for the hints. I use writeReplace() {return new BrokerObject) in my class (which is serialzable and has a fixed UID) on the server-side to generate a broker object that then should be passed to the client. The broker object is defined in an external jar which is in the classpath of the client (javaFX) and server (groovy/grails) project. It is marked serializable and as well has a fixed UID. However, I get an
{code}
java.rmi.UnmarshalException: error unmarshalling return; nested exception is:
     java.io.EOFException
     at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:173).
on the client side.
What puzzles me even more:
When I usewriteReplace() {return this.toString())
{code}
I can receive the resulting String without problems on the client side.
However, when I use
writeReplace() {return new String(this))I also get the above error.
It seems, there is some kind of incompatibility when a new Object is created. Any ideas?
Cheers
fatzopilot