Need Java File Management Help

Well, here is what I need to do. I need to code it so I can put the file path of where my program is running into a string.

And then I need it to give me a list of all the files (as a string) that have the ".t2s" extention that are in that folder.

I've tried googling the solution to my problem, but I couldn't find anything that helped. What I'm doing is making a game, and I need it to get all the saved character files from the same folder that it is in.

Thanks in advance for any help.