Have you ever wrote a super cool Java/Kotlin desktop application and packaged it in a jar just to find out that most users will not have a JRE installed?
Or have you ever found someone giving you weird bug reports because they have an outdated version of Java while you're developing for Java 11?
If you did, then you just found the solution!
Go Java Launcher is a launcher for jar files, that will search for the right JRE version and launch the jar with that version.
Now... what's the point of this if there are more mature project like launch4j?
The point is that Go Java Launcher will work even if the JRE is not installed, if it can't find a suitable JRE it will download the one you want from AdoptOpenJDK and it will install it before launching the jar, all pretty fastly and without requiring user interaction.
If you go on releases you will find the builds for windows and linux, currently it is only available for x64 machine, if you want the launcher to support more architectures...
Do a pull request, i'm too lazy to do that ;D
On windows there are a pair of downsides to using the release: if you download a release the .exe will have the default icon and no app manifest, feel free to change them with resourcehack to give the launcher the aspect of something that's part of your app.
To build this launcher you need to have Golang and Make, then run:
make windows
or:
make linux
If you don't want to install make you can simply copy the commands in the Makefile to build this program.
(But seriously... install make you'll need it sooner or later)
If you build it on windows you will be able to chose the launcher icon by replacing resources/icon.ico
For configurations you can put a file named go-java.json in the same folder where you put the launcher.
For now the json configuration file allow you to choose the java version that you want to use and the name of the jar.
The default go-java.json is available here: go-java.json