Question 1

How to run FreeJ2ME on RetroArch?

Accepted Answer

Compile the libretro core using the make instructions in the README, place freej2me-lr.jar in the system/ folder and the core file in cores/, then load J2ME files through the RetroArch interface. Note that sandboxed environments may require additional setup.

Question 2

FreeJ2ME vs KEmulator: which is better for old Java games?

Accepted Answer

FreeJ2ME is open-source and multi-frontend, ideal for retro gaming integrations like RetroArch, while KEmulator is Windows-only with a GUI focus. Choose FreeJ2ME for cross-platform flexibility, but KEmulator for easier out-of-box use on Windows.

Question 3

Can FreeJ2ME run on a Raspberry Pi?

Accepted Answer

Yes, via the SDL2 frontend—compile the SDL2 binary with make as per the README, then use freej2me-sdl.jar. This makes it suitable for embedded retro gaming setups like RetroPie.

Question 4

How to change keybindings in FreeJ2ME?

Accepted Answer

Modify the config file in the working directory or use default mappings: Q/W for softkeys, arrow keys for nav, and E/R for */#. The README includes a KEYMAP.md link for more details on customizations.

Question 5

What J2ME games work well with FreeJ2ME?

Accepted Answer

Compatibility is community-driven; check the project wiki and forum threads linked in the README for tested games. The roadmap focuses on expanding game support, but not all titles may run perfectly.

Question 6

How to compile FreeJ2ME from source on Windows?

Accepted Answer

Use MSYS2 as described in the README: install mingw-w64 and make, then run make in src/libretro to build the DLL. This requires familiarity with command-line tools and Java runtime setup.

Question 7

Does FreeJ2ME support save states or cheat codes?

Accepted Answer

It saves game data locally in the working directory, but the README doesn't mention save states or cheats. Focus is on basic emulation and preservation, so advanced features may be limited.

FreeJ2ME

What is FreeJ2ME?

Overview

Use Cases

Best For

Related Projects

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions