With the updates of Minecraft making the game more and more complex with a lot of new stuff, I never truly was satisfied with the usual ways of structuring a mod's codebase.

The ExtendedModInitializer interface is an attempt at better mod code management.

It extends ModInitializer, and as such, acts like it in your fabric.mod.json's entrypoints.

An empty ExtendedModInitializer setup looks like this:

public class MModdingExampleMod implements ExtendedModInitializer {

	@Override
	public void setupManager(ElementsManager manager) {
	}

	@Override
	public void onInitialize(AdvancedContainer mod) {
	}        
}

Let's explain what's happening in there:

• ExtendedModInitializer#setupManager(ElementsManager) is the main management upgrade part. It is a sort of standard you will be using to make your initializations, registrations, etc...
• ExtendedModInitializer#onInitialize(AdvancedContainer) is an advanced version of ModInitializer#onInitialize(ModContainer), which's last shouldn't be overridden in an extended mod initializer. It has the advantage of providing an AdvancedContainer directly, which is, as you can guess, an advanced version of a ModContainer object, providing a lot of utility methods for your mod, such as a logger and registration utils.

Tips for your entrypoint class

Here are some utility methods you can put in your entrypoint right away, they will always match your needs:

public class MModdingExampleMod implements ExtendedModInitializer {

	// ...

	public static String namespace() {
		return "mmodding_example_mod"; // Change this to match your mod's namespace/id!
	}

	public static Identifier createId(String path) {
		return Identifier.fromNamespaceAndPath(namespace(), path);
	}

	public static Identifier createTexture(String path) {
		return IdentifierUtil.texture(namespace(), path);
	}

	public static <T> ResourceKey<T> createKey(ResourceKey<? extends Registry<T>> registry, String path) {
		return ResourceKey.create(registry, createId(path));
	}
}

ElementsManager

It is the object provided in ExtendedModInitializer#ElementsManager. Its purpose is to... manage your elements 😃.

An ElementsManager has three methods:

• ElementsManager#content allows you to put a ContentProvider. More details here.
• ElementsManager#ifMoreLoaded allows you to put a ContentProvider, which would only be applied if the corresponding mod namespace is matched by Fabric Loader.
• ElementsManager#resource allows you to put a ResourceProvider for a specific Dynamic Registry. More details here.