Drawing Use case diagram

Iam developing a training program software.in that software i there will be two user .one is trainee and second one is associates.
tainee will post the details of the training in to this software and the software will send mail to all associates about this program

Yeah, great, I too is developping an App!

Is there a question here or did I read this wrong?

question is how can i draw the usecase diagram and class diagram for this application

I suggest that you get a tool that can read Javascript code to create the cases automatically. The tool I use does not do Javascript so I can't help you any further. If you want to do it by hand, I suggest trying Enterprise Architect (not sure if it directly reads Javascript code or not, our company uses it for Java). That way you can learn the framework and create the diagrams at the same time.