Awesome
roast
A JVM starter in Rust
roast
is a small executable that launches a JVM, similar to what using jpackage
would output. It uses a config file to determine some options, inspired by packr json format.
In addition to launching the JVM, it hints Windows systems with hybrid GPU setups (NVIDIA Optimus, AMD PowerXpress) to use the discrete GPU.
API
roast
will look for the following in its containing folder
Runtime
A JDK/JRE, or a minimized image from jlink
, in the runtime
folder.
JSON config file
The config file must be in the app
folder, and must have the same name as the executable, so for example, if your executable is game
(or game.exe
), the config file will be app/game.json
.
It's possible to have multiple copies of roast named differently to support different launch options on the same runtime. For example, you could have game
and game-debug
executables corresponding to app/game.json
and app/game-debug.json
.
The config file supports the following options:
classPath
: path of the jars to include in the application classpath (usually, your application jar), this is mandatorymainClass
: the package and name of the class from which to call the methodpublic static void main(String[] args)
, this is mandatoryuseZgcIfSupportedOs
: uses ZGC when supported, defaults to falseuseMainAsContextClassLoader
: sets the main class as the main thread's context class loader, defaults to falsevmArgs
: arguments to pass to the java runtime, defaults to an empty arrayargs
: arguments to the pass to main method, defaults to an empty array
For example:
{
"classPath": ["app.jar"],
"mainClass": "io.github.fourlastor.Main",
"useZgcIfSupportedOs": true,
"useMainAsContextClassLoader": false,
"vmArgs": ["-Xmx1G"],
"args": ["cli", "args"]
}