making a selenium framework in eclipse(java environment). previously used visual studio.

hi all,  I am making a selenium framework in eclipse(i.e. in java environment). previously used visual studio ( i.e. in C# environment). Do I need to have testNG / junit jars?  or only adding selenium jars will be fine?

You will need to add the test framework jars.

Building a framework is not an easy task. But that is good you are starting it.

It needs to have clear picture before putting all the things. 

What is the purpose of your automation.
What extent you are goin to automate.
Et etc...

Below link may be help full for you.
Designing Framework
http://seleniumeasy.com/tags/frameworks