net.fabricmc.loader.api

Interface LanguageAdapter

public interface LanguageAdapter

Creates instances of objects from custom notations.

It enables obtaining of other JVM languages' objects with custom instantiation logic.

A language adapter is defined as so in fabric.mod.json:

   "languageAdapter": {
     "<a key>": "<the binary name of the language adapter class>"
   }
 

Multiple keys can be present in the languageAdapter section.

In the declaration, the language adapter is referred by its binary name, such as "mypackage.MyClass$Inner". It must have a no-argument public constructor for the Loader to instantiate.

The default language adapter from Fabric Loader can accepet value as follows:

• A fully qualified reference to a class, in binary name, such as package.MyClass$Inner, where the class has a public no-argument constructor and type is assignable from the class.

  An example of an entrypoint class

  
       package net.fabricmc.example;
       import net.fabricmc.api.ModInitializer;
       public class ExampleMod implements ModInitializer {
         public ExampleMod() {} // the constructor must be public no-argument
          @Override
         public void onInitialize() {}
       }
     

  You would declare "net.fabricmc.example.ExampleMod".

  For each entrypoint reference, a new instance of the class is created. If this class implements two separate entrypoints, there will be two distinct instances of this class in two entrypoint containers.

• A fully qualified reference to a class in binary name followed by :: and a field name. The field must be static, and type must be assignable from the field's class.

  An example of an entrypoint field

  
       package net.fabricmc.example;
       import net.fabricmc.api.ModInitializer;
       public final class ExampleMod implements ModInitializer {
         public static final ExampleMod INSTANCE = new ExampleMod();
  
         private ExampleMod() {} // Doesn't need to be instantiable by loader
  
          @Override
         public void onInitialize() {}
       }
     

  You would declare "net.fabricmc.example.ExampleMod::INSTANCE".

• A fully qualified reference to a class in binary name followed by :: and a method name. The method must be capable to implement type as a method reference. If the method is not static, the class must have an accessible no-argument constructor for the Loader to create an instance.

  An example of an entrypoint method

  
       package net.fabricmc.example;
       public final class ExampleMod {
         private ExampleMod() {} // doesn't need to be instantiable by others if method is static
  
         public static void init() {}
       }
     

  You would declare "net.fabricmc.example.ExampleMod::init".

Method Summary

Modifier and Type	Method and Description
<T> T	create(ModContainer mod, String value, Class<T> type) Creates an object of type from an arbitrary string declaration.

Method Detail

create

<T> T create(ModContainer mod,
             String value,
             Class<T> type)
      throws LanguageAdapterException

Creates an object of type from an arbitrary string declaration.

Type Parameters:

T - the type

Parameters:

mod - the mod which the object is from

value - the string declaration of the object

type - the type that the created object must be an instance of

Returns:

the created object

Throws:

LanguageAdapterException - if a problem arises during creation, such as an invalid declaration