Install your tools¶
Three tools are enough, all free. Install them in this order.
1. Java 17¶
Minecraft 1.20.1 and Forge 47 run on Java 17, neither older nor newer to build a mod. Install a JDK 17 (the development kit, not just what runs Java), for example Eclipse Temurin 17 from adoptium.net.
Check in a terminal:
The answer must start with openjdk version "17.
Why exactly 17?
A mod is compiled for a precise Java version. Minecraft 1.20.1 expects 17: a mod compiled for a newer version would refuse to load.
2. A code editor: IntelliJ IDEA¶
IntelliJ IDEA (jetbrains.com/idea), in its free edition, opens a mod project as is: it understands Gradle, the tool that builds the mod and launches the game, completes your code and flags errors as you type.
And Gradle, do I install it?
No. Each mod project contains its own Gradle launcher (gradlew), which downloads the right version by itself on
first launch, then Minecraft and Forge.
3. Blender, for 3D models¶
Blender (blender.org) is used to create the shape and colours of your objects. AXION
reads the glTF 2.0 format: in Blender, File › Export › glTF 2.0, then pick .glb (a single file, the simplest)
or .gltf.
Not comfortable with Blender yet?
Start with a cube: the first addon only needs a simple shape. You will refine it later.
Ready¶
With Java 17, IntelliJ IDEA and Blender, you have everything you need for your first addon.