Class ItemCapability<T, C extends @Nullable Object>

java.lang.Object

net.neoforged.neoforge.capabilities.BaseCapability<T,C>

net.neoforged.neoforge.capabilities.ItemCapability<T,C>

Type Parameters:

T - type of queried objects

C - type of the additional context

public final class ItemCapability<T, C extends @Nullable Object>
extends BaseCapability<T,C>

An ItemCapability gives flexible access to objects of type T from item stacks.

Querying an item capability

To get an object of type T, use IItemStackExtension.getCapability(ItemCapability). For example, to query an item handler from an item stack:

ItemStack stack = ...;
IItemHandler maybeHandler = stack.getCapability(Capabilities.ItemHandler.ITEM);
if (maybeHandler != null) {
    // Use maybeHandler
}

Providing an item capability

To provide objects of type T, register providers to RegisterCapabilitiesEvent. For example:

modBus.addListener((RegisterCapabilitiesEvent event) -> {
    event.registerItem(
        Capabilities.ItemHandler.ITEM, // capability to register for
        (itemStack, context) -> <return the IItemHandler for the itemStack>,
        MY_ITEM);
});

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final Map<Item, List<ICapabilityProvider<ItemStack, C, T>>>	providers
private static final CapabilityRegistry<ItemCapability<?,?>>	registry

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ItemCapability(Identifier name, Class<T> typeClass, Class<C> contextClass)

Method Summary

Modifier and Type	Method	Description
static <T, C extends @Nullable Object> ItemCapability<T,C>	create(Identifier name, Class<T> typeClass, Class<C> contextClass)	Creates a new item capability, or gets it if it already exists.
static <T> ItemCapability<T, @Nullable Void>	createVoid(Identifier name, Class<T> typeClass)	Creates a new item capability with Void context, or gets it if it already exists.
static List<ItemCapability<?,?>>	getAll()	Returns a new immutable copy of all the currently known item capabilities.
@Nullable T	getCapability(ItemStack stack, C context)

Methods inherited from class BaseCapability

contextClass, name, typeClass

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

registry

private static final CapabilityRegistry<ItemCapability<?,?>> registry

providers

final Map<Item, List<ICapabilityProvider<ItemStack, C extends @Nullable Object, T>>> providers

Constructor Details

ItemCapability

private ItemCapability(Identifier name,
 Class<T> typeClass,
 Class<C> contextClass)

Method Details

create

public static <T, C extends @Nullable Object>
ItemCapability<T,C> create(Identifier name,
 Class<T> typeClass,
 Class<C> contextClass)

Creates a new item capability, or gets it if it already exists.

Parameters:

name - name of the capability

typeClass - type of the queried API

contextClass - type of the additional context

createVoid

public static <T> ItemCapability<T, @Nullable Void> createVoid(Identifier name,
 Class<T> typeClass)

Creates a new item capability with Void context, or gets it if it already exists. This should be used for capabilities that do not require any additional context.

See Also:

• create(Identifier, Class, Class)

getAll

public static List<ItemCapability<?,?>> getAll()

Returns a new immutable copy of all the currently known item capabilities.

Returns:

a new immutable copy of all the currently known item capabilities

getCapability

@Internal
public @Nullable T getCapability(ItemStack stack,
 C context)