Access Wideners/Transformers

Since Stonecraft version: 1.12.0

Access widening provides a way to loosen the access limits of classes, methods or fields. This includes making them public, or making them extendable (subclassable).

In Fabric, this would typically be done with Access wideners, while NeoForge uses Access Transformers. Please refer to their respective docs in order to understand the differences.

Stonecraft leverages Stonecutter and Architectury Loom, which allows you to define a different access widening file for each version supported by your mod by using variable substitution.

Setting up

important

Stonecraft and Loom will automatically convert your access wideners to access transformers for NeoForge and Forge, so you don't need to worry about that. You only need to define the access widener files for Fabric, and Stonecraft will handle the rest.

Step 1: Creating the files

In your project, create the needed files in a common folder inside resources. This depends on the versions your project is supporting.

src.main.resources
└── accesswideners/
    └── 1.19.accesswidener
    └── 1.20.accesswidener
    └── 1.21.accesswidener

Step 2: Define the variable

build.gradle.kts

val awFile = // This is the main logic to determine which access widener file to use based on the current Minecraft version.
    when {
        stonecutter.current.parsed >= "1.21" -> {
            project.rootProject.layout.projectDirectory
                .file(
                    "src/main/resources/accesswideners/1.21.accesswidener",
                )
        }

        stonecutter.current.parsed >= "1.20" -> {
            project.rootProject.layout.projectDirectory
                .file(
                    "src/main/resources/accesswideners/1.20.accesswidener",
                )
        }
        
        else -> {
            project.rootProject.layout.projectDirectory
                .file(
                    "src/main/resources/accesswideners/1.19.accesswidener",
                )
        }
    }

modSettings {
    
    // ... rest of your modSettings configuration

    accessWidenerLocation = awFile // This tells Stonecraft and Loom which AW to use
}

Opting out of automatic access widener handling

warning

This is completely optional and not recommended unless you have very specific needs

In your build.gradle.kts, you need to add the following to your modSettings:

build.gradle.kts

val awFile = // This is the main logic to determine which access widener file to use based on the current Minecraft version.
    when {
        stonecutter.current.parsed >= "1.21"-> {
            when {
                project.mod.isFabric -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesswideners/1.21.accesswidener",
                    )
                else -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesstransformers/1.21.cfg",
                    )
            }
        }

        stonecutter.current.parsed >= "1.20" -> {
            when {
                project.mod.isFabric -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesswideners/1.20.accesswidener",
                    )
                else -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesstransformers/1.20.cfg",
                    )
            }
        }
        
        else -> {
            when {
                project.mod.isFabric -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesswideners/1.19.accesswidener",
                    )
                else -> project.rootProject.layout.projectDirectory
                    .file(
                        "src/main/resources/accesstransformers/1.19.cfg",
                    )
            }
        }
    }

modSettings {

    // ... rest of your modSettings configuration
    
    accessWidenerProcessing = false // This tells Stonecraft and Loom to not handle the access widener automatically
    variableReplacements =
        mapOf(
            "awFile" to awFile.asFile
                .relativeTo(
                    project.rootProject.layout.projectDirectory
                        .dir("src/main/resources")
                        .asFile,
                ).invariantSeparatorsPath,
        )
}

This will give you access to the awFile variable in your metadata files to point them to the correct file.

Fabric

In your fabric.mod.json, you need to add the following:

fabric.mod.json

{
  "accessWidener": "${awFile}"
}

NeoForge

In your META-INF/neoforge.mods.toml, you need to add the following:

META-INF/neoforge.mods.toml

[[access-transformer]]
file="${awFile}"

Forge

For Forge, you need to rely on Stonecraft/Loom to do the work for you, you can't define the access transformer in your mods.toml file. Please refer to Step 2