Generating Java classes from WSDL issue

I have a query related to generating Java classes with wsdl files using the wsdl2java tool in Axis2. I am relatively new to learning about this.

With Axis 1.4, the wsdl2java tool generates a Proxy, Service, ServiceLocator and SoapBindingStub Java classes, whereas with Axis2 1.6, the wsdl2java tool generates a number of other Java classes such as the ServiceSkeleton, ServiceSkeletonStub, CallbackHandler, MessageReceiverInOut Java classes.

Are they both the same thing? What is the difference between the classes in Axis1.4 and Axis2 1.6? Are there any links or tutorials that goes through this in detail?

I probably wasn't clear when I first asked this question. Sorry about that.

The main issue I have is, I need help migrating an Axis project to Axis2.

I'm working on an older Axis project, and some of the Java classes were generated from WSDL using the older WSDL2Java tool.
The problem now is, Java sees that as an error, since I have the latest Axis2 version 1.6.

I've been told to regenerate the Java classes from the the WSDL file using the WSDL2Java tool found in Axis2, however, the classes
generated are completely different to the older WSDL2Java.

How would I rework my way around this? I don't feel the project would work if I replace the older classes with the newer.