Run a Java program on Manjaro

What is a jar file

A jar is java package - a zip-compressed archive - including the code for a java application.

How can I start the application

The jar requires at least JRE (Java Runtime Environment) - some requires the full JDK (Java Development Kit). A JDK contains the corresponding JRE.

If in doubt of the actual requirements of the application - install the JDK.

To install the latest JRE

sudo pacman -Syu jre-openjdk

Or the complete environment

sudo pacman -Syu jdk-openjdk

Commandline

To run the application contained in the jar

java -jar java-app.jar

Create a script and a launcher

If you want to launch the program from your menu or the terminal - create a script and a launcher as follows.

1. Create the bin folder

   mkdir ~/.local/bin

2. Move the jar to the bin folder Assuming it is in Downloads

   mv ~/Downloads/java-app.jar ~/.local/bin

3. Create the script Open your favorite text editor with a new file and save it as ~/.local/bin/java-app with below content - the "$@" ensures that any arguments to the script is passed on to the java-app.jar file

   #!/bin/sh
   java -jar ~/.local/bin/java-app.jar "$@"

4. Make the script executable

   chmod +x ~/.local/bin/java-app

5. Create the application folder

   mkdir -p ~/.local/share/applications

6. Create the desktop launcher Use the text editor to create a new file and save it as ~/.local/share/applications/java-app.desktop with below content

   [Desktop Entry]
   Encoding=UTF-8
   Name=Some Java App
   Comment=Run the java-app.jar program
   GenericName=Some Java App
   Exec=~/.local/bin/java-app
   Terminal=false
   Type=Application
   Icon=java-app-icon
   Categories=Application;
   StartupWMClass=java-app
   StartupNotify=true

Conclusion

You are now be able to run Some Java App by providing the script name and any arguments for the java-app.jar and you can find it in the system's menu tree.