This extension contains the OpenJDK 21 Java Runtime Environment (JRE) and Java Developement Kit (JDK).
OpenJDK 21 is the current long-term support (LTS) version.
For the previous LTS version, see the OpenJDK 17 extension.
For the current latest (non-LTS) version, see the OpenJDK extension.
You can bundle the JRE with your Flatpak application by adding this SDK extension to your Flatpak manifest and calling the install.sh script. For example:
{
"id" : "org.example.MyApp",
"branch" : "1.0",
"runtime" : "org.freedesktop.Platform",
"runtime-version" : "23.08",
"sdk" : "org.freedesktop.Sdk",
"sdk-extensions" : [ "org.freedesktop.Sdk.Extension.openjdk21" ],
"modules" : [ {
"name" : "openjdk",
"buildsystem" : "simple",
"build-commands" : [ "/usr/lib/sdk/openjdk21/install.sh" ]
}, {
"name" : "myapp",
"buildsystem" : "simple",
....
} ]
....
"finish-args" : [ "--env=PATH=/app/jre/bin:/usr/bin" ]
}