What is the difference between rdfs:Resource and rdfs:Class?

For example I have something like this in my application:

class X {
     public Y doY(Z z){
         //...
     }
}
x = new X();
z = new Z();
Y y = x.doY(z); //not necessary

How can I describe this structure with RDF and RDFs?

I tried to describe it with something like the following, but I don't think I do it well: (please imagine the namespaces)

Method type Class
    returnValue type Property
    returnValue domain Method
    arguments type Property
    arguments type List
    arguments domain Method

X type Class
    doY type Method
        doY domain X
        z type Z
        z member doY.arguments 

x type X
z type Z
y type Y

x.doY.arguments._1 value z
y value x.doY.returnValue

What I really need to describe REST services with JSON-LD, but I suppose I cannot do that without fully understanding RDF. (I have an existing model, it works well in theory.)

Solution

According to the w3c recommendation by RDF everything is an rdfs:Resource instance, even the rdfs:Class itself. I assume we usually don't use rdfs:Resource in our triples when we want to define a class, so I think the example was okay.

What I really need to describe REST services with JSON-LD, but I suppose I cannot do that without fully understanding RDF. (I have an existing model, it works well in theory.)

I think RDF is just a formality in by case. What really matters that if I want to write a general REST browser, then it should know a general REST vocabulary which I can describe with RDF. If I have an application specific REST client then it should know an application specific vocabulary, which has to be based on the general REST vocabulary, for example it should use the terms: resource, representation, method, link, etc... That's all I need.