22
edits
Changes
→Registry Dispatch
* BlockPlacer and BlockPlacerType
* BlockPlacer and BlockPlacerType
* ConfiguredDecorator and FeatureDecorator
* ConfiguredDecorator and FeatureDecorator
=== Registering MapCodecCodecs for Dispatch Subcodecs ===
When registering a subcodec to any dispatch codec registry, the registered subcodec should be an instance of MapCodecCodec, or the subcodec will be nested in its own object when serialized.
For example, suppose we register a single-field subcodec, where we use fieldOf-and-xmap to convert an int to our int-holding Thing:
<syntaxhighlight lang="java">
public record Thing(int n){}
public static Codec<Thing> CODEC = Codec.INT.fieldOf("n").codec().xmap(Thing::new, Thing::n);
</syntaxhighlight>
This results in this json when serialized:
<syntaxhighlight lang="json">
"some_thing":
{
"type": "ourmod:thing",
"value": {
"n": 5
}
}
</syntaxhighlight>
This occurs because xmap does not produce a MapCodecCodec, and if this nested object is not desired, then our registered subcodec must be a MapCodecCodec.
However, fieldOf() produces a MapCodec, which has a codec() method, which does produce a MapCodecCodec. We can rearrange our codec builder, which then produces a cleaner json:
<syntaxhighlight lang="java">
public static Codec<Thing> CODEC = Codec.INT // Primitive codec
.fieldOf("n") // MapCodec
.xmap(Thing::new, Thing::n) // MapCodec
.codec(); // MapCodecCodec! That's what we want.
</syntaxhighlight>
<syntaxhighlight lang="json">
"some_thing":
{
"type": "ourmod:thing",
"n": 5
}
</syntaxhighlight>
RecordCodecBuilder also produces MapCodecCodecs.
=External Links=
=External Links=
* [https://github.com/Mojang/DataFixerUpper/blob/master/src/main/java/com/mojang/serialization/Codec.java Codecs in Mojang's official public DataFixerUpper repository]
* [https://github.com/Mojang/DataFixerUpper/blob/master/src/main/java/com/mojang/serialization/Codec.java Codecs in Mojang's official public DataFixerUpper repository]
* [https://kvverti.github.io/Documented-DataFixerUpper/snapshot/com/mojang/serialization/Codec.html#flatXmap-java.util.function.Function-java.util.function.Function- Unofficial Codec Javadocs]
* [https://kvverti.github.io/Documented-DataFixerUpper/snapshot/com/mojang/serialization/Codec.html#flatXmap-java.util.function.Function-java.util.function.Function- Unofficial Codec Javadocs]