Hi Uladzimir_So if you know enough java to be asking about pack() then why did you post this asking to learn about oop concepts. Do you know the basics of java, do you just have some experience with programing in general? If someone's going to give you an appropriate text (book or online) to help you learn they need to know where you are with java and OOP in general.
Thanks for ur response... I'll follow the link... but
can u suggest some thing for OOPS concept (ONLINE
prefferd) or any other material.