Get a ClassLoader determined at runtime into the classpath

Question

The class MyClass is dertermined at runtime and loaded from an URLClassLoader, which can not be in the original classpath.
An objectInputStream is deserializing classes from that type, but it throws an exception and can not resolve that class, because it isn't in the classpath.
Because the URLClassLoader is a JarFile, it is easy to iterate to them, but trying to do loadClass for each of them didn't enable the objectInputStream to recognize them.
Some ideas where to create bytestreams from my class and extend a classloader to load those, but is there no easier way to get a classloader into the classpath or a single class into the list of classes of the classpath?

Answer 1

I think that the main problem is that the ObjectInputStream cannot find the proper ClassLoader when deserializing.
I have never tried it, but I think what needs to be done is to set the ContextClassLoader property of the thread that is doing the deserialization.
Something like this:
ClassLoader cl = new URLClassLoader(....);
Thread t = Thread.currentThread();
t.setContextClassLoader(cl);
ObjectInputStream ois = new ObjectInputStream(....);
Object o = ois.readObject();
.