fabric/fabric-api-lookup-api-v1
Jonathan Coates bb43a8b9bf Check for the correct BE type in the lookup API (#3510)
The block lookup API's registerForBlockEntities method currently just
registers the passed provider for each valid block for that block
entity.

However, in some situations (such as update suppression or a misbehaving
mod), the wrong block entity will be present for one of these blocks.
This means that the (incorrect) block entity will be passed off to the
provider. Providers (especially those registered with
registerForBlockEntity) will often blind-cast the supplied BE, leading
to crashes.

While the wrong BE being present is a bug, we should follow vanilla's
lead and handle this more gracefully. In this case, we just check
whether the correct BE type is present before forwarding it to the
main provider.

(cherry picked from commit 82b1bb3ec3)
2024-01-11 15:50:41 +00:00
..
src Check for the correct BE type in the lookup API (#3510) 2024-01-11 15:50:41 +00:00
build.gradle Update to loom 1.3 and use Mod Publish Plugin (#3158) 2023-08-02 18:51:21 +01:00
README.md Entity API Lookup (#1836) 2021-12-03 13:38:35 +00:00

Fabric API Lookup API (v1)

This module allows API instances to be associated with game objects without specifying how the association is implemented. This is useful when the same API could be implemented more than once or implemented in different ways. See also the package-info.java file.

  • What we call an API is any object that can be offered or queried, possibly by different mods, to be used in an agreed-upon manner.
  • This module allows flexible retrieving of such APIs, represented by the generic type A, from blocks in the world or from item stacks.
  • It also provides building blocks for defining custom ways of retrieving APIs from other game objects.

Retrieving APIs from blocks

See the javadoc of BlockApiLookup for a full usage example.

BlockApiLookup

The primary way of querying API instances for blocks in the world. It exposes a find function to retrieve an API instance, and multiple register* functions to register APIs for blocks and block entities.

Instances can be obtained using the get function.

BlockApiCache

A BlockApiLookup bound to a position and a server world, allowing much faster repeated API queries.

Retrieving APIs from items

See the javadoc of ItemApiLookup for a full usage example.

ItemApiLookup

The way to query API instances from item stacks. It exposes a find function to retrieve an API instance, and multiple register* functions to register APIs for items.

Retrieving APIs from entities

See the javadoc of EntityApiLookup for a full usage example.

EntityApiLookup

The way to query API instances from entities. Exposes a find function to retrieve an API instance, and multiple register* functions to register APIs for entity types.

Retrieving APIs from custom objects

The subpackage custom provides helper classes to accelerate implementations of ApiLookups for custom objects, similar to the existing BlockApiLookup, but with different query parameters.

ApiLookupMap

A map meant to be used as the backing storage for custom ApiLookup instances, to implement a custom equivalent of BlockApiLookup#get.

ApiProviderMap

A fast thread-safe copy-on-write map meant to be used as the backing storage for registered providers.