This page was provided by a JMRI users group member and describes how he installed JMRI on Linux Mint.
Installing JMRI on a Linux Mint
1) The current versions of JMRI need to have Java 1.8 installed. To do this from the command line, enter:
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer
2) Download JMRI from http://jmri.org/download/index.shtml and save the file.
3) Double click the downloaded tarball, that will open the archive manager program. Extract the JMRI tarball to your home directory, or some other directory. The extract program will create a JMRI folder in this location.
4) Open a terminal session and type: sudo adduser $USER dialout (it may ask you for a password).
This should give permissions to the com port.
5) Reboot the computer
6) JMRI can now be run by double clicking on the DecoderPro3 icon in the JMRI folder. You have the option of simply running the program or running in Terminal, I would suggest running it in Terminal as it will show any error messages in the terminal window.
7) JMRI will ask for preferences to be set up, select your Manufacturer of your DCC system (eg. Digitrax, NCE, etc.), then select how you are connecting to the DCC system (LocoBuffer, LocoNet PR3, etc.)
Then select the serial port from the drop down, it should be something like "/dev/ttyACM0"
Now select your command station type, (DCS50, PR3, etc.) leave the Connection Prefix and Connection Name they way they are.
8) It will ask you to restart JMRI. After the restart of JMRI, if all goes well, you should be running JMRI.