What is Class Descriptor?

Question

What is Class Descriptor?

Is it a Class object of a particular class?

Answer 1

You've given very little context, but "class descriptor" can be a termed used to describe the data necessary to deserialize an object:

http://java.sun.com/javase/6/docs/platform/serialization/spec/class.html

In that case, a "class descriptor" is actually java.io.ObjectStreamClass. An ObjectStreamClass describes a class, but it is different from the class itself.