Download and extract this repo (you can also just download this repo as zip and unpack)
cd ~ && git clone https://github.com/vipaoL/j2me-wrapper-linux.git j2me # you can set an other name
Run the installer (you will need to run in again if you rename or move the installation folder)
cd j2me && ./install.sh
Right click on a j2me application, choose "open with "Install J2ME app"". The app will appear in your system's applications list
./wrapper-files/install-j2me-jar.sh -y path/to/j2me-app.jar
you can install my game for test: https://github.com/vipaoL/mobap-game/releases
Delete "j2me" folder, ~/.local/share/applications/add-j2me-jar.desktop, ~/.local/share/applications/midlet-manager.desktop and ~/.local/share/applications/*_J2ME.desktop