Run Configurations

Run configurations define how an instance of the game is going to run. This includes arguments, working directories, task names, etc. Run configurations are defined within the minecraft.runs block. While no runs are configured by default, Forge does provide the configurations client, server, data, or gameTestServer.

minecraft {
    // ...
    runs {
        // Configure runs here
    }
}

Run configurations can be added similar to any NamedDomainObjectContainer using closures.

// Inside the minecraft block
runs {
    // Creates or configures the run configuration named 'client'
    client {
        // Configure run
    }
}

The following configurations properties are available:

// Inside the runs block
client {
    // The name of the Gradle run tasks,
    // Defaults to 'runX' where X is the container name
    taskName 'runThing'

    // Sets the entrypoint of the program to launch
    // Forge sets userdev main to be 'cpw.mods.bootstraplauncher.BootstrapLauncher'
    main 'com.example.Main'

    // Sets the working directory of the config
    // Defaults to './run'
    workingDirectory 'run'

    // Sets the name of the module for IntelliJ IDEA to configure for its runs
    // Defaults to '<project_name>.main'
    ideaModule 'example.main'

    // Sets whether this should run a Minecraft client
    // If not specified, checks the following
    // - Is there an environment property 'thing' that contains 'client'
    // - Does the configuration name contain 'client'
    // - Is main set to 'mcp.client.Start'
    // - Is main set to 'net.minecraft.client.main.Main'
    client true

    // Set the parent of this configuration to inherit from
    parent runs.example

    // Sets the children of this configuration
    children runs.child

    // Merges this configuration and specifies whether to overwrite existing properties
    merge runs.server, true

    // If not false, will merge the arguments of the parent with this configuration
    inheritArgs false

    // If not false, will merge the JVM arguments of the parent with this configuration
    inheritJvmArgs false

    // Adds a sourceset to the classpath
    // If none is specified, adds sourceSet.main
    source sourceSets.api

    // Sets an environment property for the run
    // Value will be interpreted as a file or a string
    environment 'envKey', 'value'

    // Sets a system property
    // Value will be interpreted as a file or a string
    property 'propKey', 'value'

    // Sets an argument to be passed into the application
    // Can specify multiple with 'args'
    arg 'hello'

    // Sets a JVM argument
    // Can specify multiple with 'jvmArgs'
    jvmArg '-Xmx2G'

    // Sets a token
    // Currently, the following tokens are being used:
    // - runtime_classpath
    // - minecraft_classpath
    token 'tokenKey', 'value'

    // Sets a token that's lazily initialized
    // Should usually be used instead of 'token', for example when the token resolves Gradle configurations
    lazyToken('lazyTokenKey') {
      'value'
    }

    // If not false, Gradle will stop once the process has finished
    forceExit true

    // If true, compile all projects instead of for the current task
    // This is only used by IntelliJ IDEA
    buildAllProjects false
}

tip

You can see a list of all configured userdev properties within the MinecraftForge buildscript.

Mod Configurations

A mod in the current environment can be added using the mods block within a Run configuration. Mod blocks are also NamedDomainObjectContainers.

// Inside the runs block
client {
    // ...

    mods {
        // Configures the 'example' mod
        example {
            // Add a source set to a mod's sources
            // This is recommended over manually adding classes and resources
            source sourceSets.main

            // Sets the location of the mod's classes
            classes sourceSets.api.output

            // Sets the location of the mod's resources
            resources files('./my_resources')
        }
    }
}