Do you have an average programming experience and want to start game development but you don't know where to start?
Then this list is for you: http://inventwithpython.com/blog/2012/02/20/i-need-practice-programming-49-ideas-for-game-clones-to-code/
It's a list that feature 49 games that you can clone to gain experience in game programming. The list is intended to be for python programmers but you shouldn't have problems to make it in java.
It's a great game programming exercise because the difficulty of each game increases as you go down the list.
Good luck and happy game development