Differences

This shows you the differences between two versions of the page.

--- tutorial:mixin_accessors [2020/08/05 22:26] – created emmanuelmess
+++ tutorial:mixin_accessors [2022/04/29 09:54] (current) – [Mixin Accessors] solidblock
@@ Line 1: / Line 1: @@
-====== Mixin Accessors ======
+====== Mixin Accessors & Invokers ======
+Mixin accessors and invokers allow you to access fields or invoke methods that are not visible (private) or final.
-===== Introduction =====
+===== Accessor =====
+''@Accessor'' allows you to access fields. Suppose we want to access ''itemUseCooldown'' field of ''MinecraftClient'' class.
-A type of mixin allows to you to access variables that are not visible (private) or final:
+==== Getting a value from the field ====
 <code java>
-@Mixin(StructuresConfig.class)
+@Mixin(MinecraftClient.class)
-public interface StructuresConfigAccessor {
+public interface MinecraftClientAccessor {
-    @Accessor("DEFAULT_STRUCTURES")
+    @Accessor
-    public static void setDefaultStructures(ImmutableMap<StructureFeature<?>, StructureConfig> defaultStructures) {
+    int getItemUseCooldown();
-        throw new IllegalAccessError();
-    }
 }
 </code>
-The error will never be thrown, you can use the function.
+Usage:
+<code java>
+int itemUseCooldown = ((MinecraftClientAccessor) MinecraftClient.getInstance()).getItemUseCooldown();
+</code>
+==== Setting a value to the field ====
+<code java>
+@Mixin(MinecraftClient.class)
+public interface MinecraftClientAccessor {
+    @Accessor("itemUseCooldown")
+    public void setItemUseCooldown(int itemUseCooldown);
+}
+</code>
+Usage:
+<code java>
+((MinecraftClientAccessor) MinecraftClient.getInstance()).setItemUseCooldown(100);
+</code>
+===== Accessor for static fields =====
+Suppose we want to access ''BIOMES'' field of ''VanillaLayeredBiomeSource'' class.
+==== Getting a value from the field ====
+<code java>
+@Mixin(VanillaLayeredBiomeSource.class)
+public interface VanillaLayeredBiomeSourceAccessor {
+  @Accessor("BIOMES")
+  public static List<RegistryKey<Biome>> getBiomes() {
+    throw new AssertionError();
+  }
+}
+</code>
+Usage:
+<code java>
+List<RegistryKey<Biome>> biomes = VanillaLayeredBiomeSourceAccessor.getBiomes();
+</code>
+==== Setting a value to the field ====
+<code java>
+@Mixin(VanillaLayeredBiomeSource.class)
+public interface VanillaLayeredBiomeSourceAccessor {
+  @Accessor("BIOMES")
+  public static void setBiomes(List<RegistryKey<Biome>> biomes) {
+    throw new AssertionError();
+  }
+}
+</code>
+Usage:
+<code java>
+VanillaLayeredBiomeSourceAccessor.setBiomes(biomes);
+</code>
+===== Invoker =====
+''@Invoker'' allows you to access methods. Suppose we want to invoke ''teleportTo'' method of ''EndermanEntity'' class.
+<code java>
+@Mixin(EndermanEntity.class)
+public interface EndermanEntityInvoker {
+  @Invoker("teleportTo")
+  public boolean invokeTeleportTo(double x, double y, double z);
+}
+</code>
+Usage:
+<code java>
+EndermanEntity enderman = ...;
+((EndermanEntityInvoker) enderman).invokeTeleportTo(0.0D, 70.0D, 0.0D);
+</code>
+===== Invoker for static methods =====
+Suppose we want to invoke ''registerPotionType'' method of ''BrewingRecipeRegistry'' class.
+<code java>
+@Mixin(BrewingRecipeRegistry.class)
+public interface BrewingRecipeRegistryInvoker {
+  @Invoker("registerPotionType")
+  public static void invokeRegisterPotionType(Item item) {
+    throw new AssertionError();
+  }
+}
+</code>
+Usage:
+<code java>
+BrewingRecipeRegistryInvoker.invokeRegisterPotionType(item);
+</code>