Developers
10 TOP-LEVEL ITEMSResource API
The Resource API is the type-abstraction layer Croparia IF uses to support multiple resource kinds and the differences they may have across mod platforms.
At the moment it supports items through ItemSpec and fluids through FluidSpec.
Architecture
The Resource API is made of TypeToken and TypedResource.
TypeToken: the ID of a resource kind. If two resources share the same type token, they are guaranteed to belong to the same kind.TypedResource: one differentiated instance of that kind, used to tell apart resources that share a kind but still cannot merge. For example,ItemSpecandFluidSpec.
For example, an Earth Elemental Gem and a Water Elemental Gem are both item ItemSpecs. Their TypeToken is the same and equals croparia:item_spec.
However, their typed resources differ: resource: "croparia:gem_earth" versus resource: "croparia:gem_water".
Note: TypedResource is only responsible for resource identity and merge-related data such as components. It does not represent a resource amount.
Add another resource type
Croparia IF only ships built-in support for item ItemSpec and fluid FluidSpec. If you want to add another resource kind, the pattern below is the intended starting point.
1. Create a typed resource class TypedResource
Create a class that implements TypedResource<T>, where the generic T is the underlying resource class. For example, ItemSpec uses Item, and FluidSpec uses Fluid.
public class MyResource implements TypedResource<Kind> {
public static final MapCodec<MyResource> CODEC_COMP = RecordCodecBuilder.mapCodec(instance -> instance.group(
Identifier.CODEC.fieldOf("id").forGetter(myResource -> myResource.getResource().builtInRegistryHolder().key().location())
).apply(instance, id -> new MyResource(BuiltInRegistries.KIND.getValue(id))));
@NotNull
private final Kind kind;
private MyResource() {
this.kind = Kind.EMPTY;
}
public MyResource(@NotNull Kind kind) {
this.kind = kind;
}
@Override
public MapCodec<MyResource> getCodec() {
return CODEC_COMP;
}
@Override
@NotNull
public Kind getResource() {
return this.kind;
}
@Override
public boolean equals(Object o) {
if (!(o instanceof MyResource resource)) return false;
if (this.isEmpty()) return resource.isEmpty();
return Objects.equals(kind, resource.kind);
}
@Override
public int hashCode() {
if (this.isEmpty()) return 0;
return Objects.hash(kind);
}
}2. Register the type token
public class MyResource implements TypedResource<Kind> {
public static final MyResource EMPTY = new MyResource(); // An instance used to represent an empty resource
public static final TypeToken<MyResource> TYPE = TypeToken.register(Identifier.of("modid:my_resource"), EMPTY, CODEC_COMP).orElseThrow();
@Override
public TypeToken<MyResource> getType() {
return TYPE;
}
// ...
}