JAXB Object (not strongly typed) within class creating MarshalException

I have a colleague that is trying to get JAXB to create XML and then create=
 the class back again where one of the member variables will just be an Obj=
ect. That is, it will not be strongly typed and it will contain a myriad o=
f different types depending on what the XML coming in contains. However, a=
 simple example results in a MarshalException with linked exception: JAXBEx=
ception: class (any class here) nor any of its super class is known to this=
 context. How can this be solved? An example of what is being tried is be=
low. Thank you for your help!

<code>
package com.hp.asi.ui.hpicsm.rmi.impl;

 

import java.io.StringWriter;

import java.util.ArrayList;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

 

import javax.xml.bind.JAXBContext;

import javax.xml.bind.Marshaller;

import javax.xml.bind.annotation.XmlAnyElement;

import javax.xml.bind.annotation.XmlElement;

import javax.xml.bind.annotation.XmlRootElement;

import javax.xml.bind.annotation.XmlSeeAlso;

 

public class testExample {

    public static void main(String[] args) {

        testExample ex = new testExample();

        

        ex.doIt();

    }

    

    public void doIt() {

        try {

        JAXBContext jaxbContext = JAXBContext.newInstance(testXML.class);

        Marshaller jaxbMarshaller = jaxbContext.createMarshaller();

        jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);

        StringWriter writer = new StringWriter();

        

        Set<String> y = new HashSet<String>();

        y.add("hello");

        y.add("world");

        testXML x = new testXML(y);

        

        jaxbMarshaller.marshal(x, writer);

        

        System.out.println(writer.getBuffer().toString());

 

        } catch (Exception e) {

            System.out.println(e);

        }

 

    }

    

    @XmlRootElement

    public static class testXML {

        @XmlElement

        private Object testVal;

        

        public testXML(){

            

        }

        

        public testXML(Object y) {

            this.testVal = y;

        }

    }

}
</code>