This is a plain and simple Space Invaders emulator written in Java. The emulator is almost complete. The sound is not perfectly emulated.
The emulator can be run from here: https://mekong.rmit.edu.vn/~v00132/invaders/
The ROMs seem to be available on the Internet. They need to be copied into the src/spaceinvaders/roms directory, before the project is build. The samples need to be copied into the src/spaceinvaders/samples directory.