I was reading a lot of information on the Internet, I promise, but I didn't find any post or tutorial in which appears How to write Java RESTful Based Axis2 Web Service
I don't know if this task has sense, because I have only read about RESTful Web Services or Web Services based on Axis2. It could be I have mixing differents ideas about how to develop Web Services and so, I need help. What can I do? Where can I learn how to develop a RESTful Web Service based on Axis2?
You can't write a RESTful Web Service using Axis2. Axis2 is suited for SOAP web services.
For RESTful Web Services you have to use some other framework like Jersey
Edit: it seems you can indeed write a REST WS using Axis2 (yet Axis2 is mostly used for SOAP services).