8-bit Graphical API for Java
Source code of the chapters of the book 3D Game Development with LWJGL
SJCE - free portable cross-platform graphical chess game, 100% Java.
Map Generation Application and API
Wonderful Java Tic Tac Toe game
John Conway's Game of Life illustrated with Bison
OpenQuest is a computer game conversion of the board game HeroQuest.
Extensive Java chess database libraries.
Sudokuki is a free graphical SUDOKU game
A collection of all maps and games made for the TripleA game engine
An online multiplayer turn based strategy game and board game engine.
Neo Modding API for Minecraft: Java Edition, based on Forge
Small Java game such as "Connect Four" but something differently.
Two projects in one so far: to learn foreign words and read books
Take the chess graphism, and use it with a chess engine.