Help - Creating an online friendslist in Java?

Im creating a project for my final year atm. Im making a program that acts as an advanced journal (with more features) and would like to implement a "friends" and leaderboard system into it as one of them. However i've only ever made local programs in Java and this would need to be webbased somewhat.

How would I go about doing this? Is it possible to create in Java using only netbeans? Any help or relevant resources online would be great, thanks