3 files changed, 81 insertions, 1 deletions
diff --git a/src/main/kotlin/thedarkcolour/kotlinforforge/AutoKotlinEventBusSubscriber.kt b/src/main/kotlin/thedarkcolour/kotlinforforge/AutoKotlinEventBusSubscriber.kt
index e36f9ce..46cdc4d 100644
--- a/src/main/kotlin/thedarkcolour/kotlinforforge/AutoKotlinEventBusSubscriber.kt
+++ b/src/main/kotlin/thedarkcolour/kotlinforforge/AutoKotlinEventBusSubscriber.kt
@@ -17,7 +17,7 @@ import java.util.stream.Collectors
  * Handles [net.minecraftforge.fml.common.Mod.EventBusSubscriber]
  */
 @Suppress("unused")
-object AutoKotlinEventBusSubscriber {
+internal object AutoKotlinEventBusSubscriber {
     private val EVENT_BUS_SUBSCRIBER: Type = Type.getType(Mod.EventBusSubscriber::class.java)
 
     /**
diff --git a/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtDeferredRegister.kt b/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtDeferredRegister.kt
new file mode 100644
index 0000000..dedfb27
--- /dev/null
+++ b/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtDeferredRegister.kt
@@ -0,0 +1,34 @@
+package thedarkcolour.kotlinforforge.registry
+
+import net.minecraft.util.ResourceLocation
+import net.minecraftforge.event.RegistryEvent
+import net.minecraftforge.eventbus.api.IEventBus
+import net.minecraftforge.registries.IForgeRegistry
+import net.minecraftforge.registries.IForgeRegistryEntry
+import java.util.*
+import java.util.function.Supplier
+import kotlin.collections.LinkedHashMap
+
+/**
+ * @see [net.minecraftforge.registries.DeferredRegister] for example use
+ */
+class KtDeferredRegister<T : IForgeRegistryEntry<T>>(private val registry: IForgeRegistry<T>, private val modid: String) {
+    private val entries: MutableMap<KtRegistryObject<T>, Supplier<out T>> = LinkedHashMap()
+    val entriesView: Set<KtRegistryObject<T>> = Collections.unmodifiableSet(entries.keys)
+
+    fun register(name: String, supplier: Supplier<out T>): KtRegistryObject<T> {
+        val key = ResourceLocation(modid, name)
+        val obj = KtRegistryObject(key, registry)
+        require(entries.putIfAbsent(obj, Supplier { supplier.get().setRegistryName(key) }) == null) { "Duplicate registration $name" }
+        return obj
+    }
+
+    fun register(bus: IEventBus) = bus.addListener(::addEntries)
+
+    private fun addEntries(event: RegistryEvent.Register<T>) {
+        for (entry in entries.entries) {
+            registry.register(entry.value.get())
+            entry.key.refresh(registry)
+        }
+    }
+}
+\ No newline at end of file
diff --git a/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtRegistryObject.kt b/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtRegistryObject.kt
new file mode 100644
index 0000000..0b44705
--- /dev/null
+++ b/src/main/kotlin/thedarkcolour/kotlinforforge/registry/KtRegistryObject.kt
@@ -0,0 +1,46 @@
+package thedarkcolour.kotlinforforge.registry
+
+import net.minecraft.util.ResourceLocation
+import net.minecraftforge.registries.IForgeRegistry
+import net.minecraftforge.registries.IForgeRegistryEntry
+import net.minecraftforge.registries.ObjectHolderRegistry
+import net.minecraftforge.registries.RegistryManager
+import java.util.function.Supplier
+
+/**
+ * An alternative to DeferredRegistry that enforces non-nullability.
+ */
+open class KtRegistryObject<T : IForgeRegistryEntry<T>>(private val name: ResourceLocation, private val registry: IForgeRegistry<T>) : Supplier<T> {
+    private lateinit var value: T
+
+    constructor(name: String, registry: IForgeRegistry<T>) : this(ResourceLocation(name), registry)
+
+    constructor(name: String, registryType: Supplier<Class<out T>>) : this(ResourceLocation(name), RegistryManager.ACTIVE.getRegistry(registryType.get()) as IForgeRegistry<T>)
+
+    init {
+        ObjectHolderRegistry.addHandler { predicate ->
+            if (predicate.test(registry.registryName)) {
+                value = registry.getValue(name)!!
+            }
+        }
+    }
+
+    override fun get(): T = value
+
+    fun refresh(registry: IForgeRegistry<out T>) {
+        value = registry.getValue(name)!!
+    }
+
+    override fun equals(other: Any?): Boolean {
+        return when (other) {
+            other === this -> true
+            other?.javaClass != javaClass -> false
+            (other as KtRegistryObject<*>).name != name -> false
+            else -> true
+        }
+    }
+
+    override fun hashCode(): Int {
+        return name.hashCode()
+    }
+}
+\ No newline at end of file