how to update single file on NetWeaver(2004s)

Hi,

I have deployed my project abc.ear on NetWeaver(2004s) through visual admin.

Now i want to change two (.class) files.For this , I found one option single update file on visual admin. But I am not understanding the option given there to select and replace the file.

Can anybody tell me the details steps that I should follow in order to change 2 files?

I really appricate if anybody solve my problem as i have to change the file again and again. Now I every time undeploy the application, make the changes and again deploy the application.