A very powerful and easy to use command based configuration library for servers and clients.

To start, create a new class. This will be the class where all your configurations are stored. For this example, we'll call this class Configs. Make sure that this class is public! Next, create a field for your configuration entry. Mark this field with the annotation @Config. The initial value of the field will be used as default (fallback) value.

public class Configs {
    @Config
    public static String exampleString = "default";
}

Finally, in your mod's onInitialize(Client) method, register the Configs class. Replace <mod id> with your mod's id.

new ModConfigBuilder(<mod id>, Configs.class).build();

That's it! Now you can access exampleString through Configs.exampleString. You can edit exampleString by executing the following command.

/(c)config <mod id> exampleString set <string>

This mod also supports the use of Collections and Maps as variable types. These configurations will have the options add, put and remove available. Moreover, you can define your own (de)serialisers to create configurations with arbitrary types. To do this, all you have to do is register the (de)serialiser when you build your config. For instance, to create a variable with type Block you can do

new ModConfigBuilder(<mod id>, Configs.class)
    .registerTypeHierarchyWithArgument(Block.class, new BlockAdapter(), new Pair<>(BlockArgumentType::block, BlockArgumentType::getBlock))
    .build();

where BlockAdapter extends TypeAdapter<Block> and BlockArgumentType implements ArgumentType<Block>. See these tests for a complete picture.

Furthermore, you can completely change the behaviour of updating your config values by creating your own methods. Simply add one or more of setter, adder, putter or remover as attribute to your @Config annotation. A great use for this would be adding key-pair entries to a Map based on a single value. Consider the following configuration.

@Config(putter = @Config.Putter("none"), adder = @Config.Adder("customMapAdder"))
public static Map<String, String> exampleMapAdder = new HashMap<>(Map.of("a", "A", "b", "B"));
public static void customMapAdder(String string) {
    exampleMapAdder.put(string.toLowerCase(Locale.ROOT), string.toUpperCase(Locale.ROOT));
}

The value of "none" for the putter indicates that no putter will be available. This way, you can use this Map in your code like usual, and add values to it using /(c)config <mod id> exampleMapAdder add <string>. For more details, see the JavaDocs for @Config.

The parameters of the update method can also be customised.

@Config(adder = @Config.Adder(value = "customTypeAdder", type = int.class))
public static Collection<String> exampleCustomType = new ArrayList<>(List.of("%", "@"));
public static void customTypeAdder(int codepoint) {
    exampleCustomType.add(Character.toString(codepoint));
}

For putters, there are separate key and value type attributes.

Replace ${version} with the artifact version.

You may choose between my own maven repository and GitHub's package repository.

repositories {
    maven {
        url 'https://maven.xpple.dev/maven2'
    }
}

repositories {
    maven {
        url 'https://maven.pkg.github.com/xpple/BetterConfig'
        credentials {
            username = project.findProperty("gpr.user") ?: System.getenv("USERNAME")
            password = project.findProperty("gpr.key") ?: System.getenv("TOKEN")
        }
    }
}

Import it:

dependencies {
    include modImplementation('dev.xpple:betterconfig:${version}')
}