Cleanup IForgeTagBuilder code style.

src/main/java/net/minecraftforge/common/ForgeHooks.java

@@ -39,7 +39,6 @@ import com.google.common.collect.Lists;
 import com.google.common.collect.Queues;
 import com.google.common.collect.Sets;
 import com.google.gson.Gson;
-import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParseException;
@@ -47,8 +46,6 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import net.minecraft.advancements.Advancement;
 import net.minecraft.block.Block;
-import net.minecraft.client.renderer.model.Material;
-import net.minecraft.client.renderer.texture.AtlasTexture;
 import net.minecraft.fluid.*;
 import net.minecraft.util.CachedBlockInfo;
 import net.minecraft.block.BlockState;
@@ -119,7 +116,6 @@ import net.minecraft.world.dimension.DimensionType;
 import net.minecraft.world.storage.loot.LootContext;
 import net.minecraft.world.storage.loot.LootTable;
 import net.minecraft.world.storage.loot.LootTableManager;
-import net.minecraftforge.common.data.IOptionalTagEntry;
 import net.minecraftforge.common.loot.IGlobalLootModifier;
 import net.minecraftforge.common.loot.LootModifierManager;
 import net.minecraftforge.common.util.BlockSnapshot;
@@ -1089,6 +1085,7 @@ public class ForgeHooks
         return res == Result.DEFAULT ? 0 : res == Result.DENY ? -1 : 1;
     }
 
+    @SuppressWarnings("deprecation")
     public static <T> void deserializeTagAdditions(Tag.Builder<T> builder, Function<ResourceLocation, Optional<T>> valueGetter, JsonObject json)
     {
         if (json.has("optional"))
@@ -1177,6 +1174,7 @@ public class ForgeHooks
         }
     }
 
+    @SuppressWarnings("deprecation")
     public static synchronized void updateBurns()
     {
         VANILLA_BURNS.clear();

src/main/java/net/minecraftforge/common/data/IOptionalTagEntry.java

@@ -2,7 +2,7 @@ package net.minecraftforge.common.data;
 
 import net.minecraft.tags.Tag.ITagEntry;
 
-public interface IOptionalTagEntry<T> extends ITagEntry<T>
-{
-
-}
+/**
+ * Marker class used by Forge to make a tag entry optional at runtime
+ */
+public interface IOptionalTagEntry<T> extends ITagEntry<T> {}

src/main/java/net/minecraftforge/common/extensions/IForgeTagBuilder.java

@@ -1,5 +1,6 @@
 package net.minecraftforge.common.extensions;
 
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Optional;
 import java.util.function.Function;
@@ -9,77 +10,80 @@ import javax.annotation.Nonnull;
 import com.google.gson.JsonArray;
 
 import net.minecraft.tags.Tag;
+import net.minecraft.tags.TagCollection;
 import net.minecraft.util.ResourceLocation;
 import net.minecraftforge.common.data.IOptionalTagEntry;
 
 public interface IForgeTagBuilder<T>
-{    
-    default Tag.Builder<T> addOptional(Function<ResourceLocation, Optional<T>> valueGetter, Collection<ResourceLocation> locations)
+{
+
+    default Tag.Builder<T> addOptional(final TagCollection<T> collection, final ResourceLocation... locations)
     {
-        return ((Tag.Builder<T>)this).add(new OptionalListEntry<>(locations, valueGetter));
+        return addOptional(collection, Arrays.asList(locations));
+    }
+
+    default Tag.Builder<T> addOptional(final TagCollection<T> collection, final Collection<ResourceLocation> locations)
+    {
+        return addOptional(collection.getEntryLookup(), locations);
+    }
+
+    @Deprecated //Use the TagCollection version
+    default Tag.Builder<T> addOptional(final Function<ResourceLocation, Optional<T>> entryLookup, final Collection<ResourceLocation> locations)
+    {
+        return ((Tag.Builder<T>)this).add(new IOptionalTagEntry<T>() {
+            @Override
+            public void populate(Collection<T> itemsIn)
+            {
+                locations.stream().map(entryLookup).forEach(e -> e.ifPresent(itemsIn::add));
+            }
+
+            @Override
+            public void serialize(JsonArray array, Function<T, ResourceLocation> getNameForObject)
+            {
+                locations.stream().map(ResourceLocation::toString).forEach(array::add);
+            }
+        });
+    }
+
+    default Tag.Builder<T> addOptionalTag(final TagCollection<T> collection, @SuppressWarnings("unchecked") final Tag<T>... tags)
+    {
+        for (Tag<T> tag : tags)
+            addOptionalTag(tag.getId());
+        return ((Tag.Builder<T>)this);
+    }
+
+    default Tag.Builder<T> addOptionalTag(final ResourceLocation... tags)
+    {
+        for (ResourceLocation rl : tags)
+            addOptionalTag(rl);
+        return ((Tag.Builder<T>)this);
     }
 
     default Tag.Builder<T> addOptionalTag(ResourceLocation tag)
     {
-        return ((Tag.Builder<T>)this).add(new OptionalTagEntry<>(tag));
-    }
-}
-
-class OptionalListEntry<T> implements IOptionalTagEntry<T>
-{
-    private final Collection<ResourceLocation> names;
-    private final Function<ResourceLocation, Optional<T>> valueGetter;
-
-    OptionalListEntry(Collection<ResourceLocation> names, Function<ResourceLocation, Optional<T>> valueGetter)
-    {
-        this.names = names;
-        this.valueGetter = valueGetter;
-    }
-
-    @Override
-    public void populate(Collection<T> itemsIn)
-    {
-        for (ResourceLocation rl : names)
-        {
-            valueGetter.apply(rl).ifPresent(itemsIn::add);
-        }
-    }
-
-    @Override
-    public void serialize(JsonArray array, Function<T, ResourceLocation> getNameForObject)
-    {
-        for (ResourceLocation rl : names)
-        {
-            array.add(rl.toString());
-        }
-    }
-}
-
-class OptionalTagEntry<T> extends Tag.TagEntry<T> implements IOptionalTagEntry<T>
-{
-    private Tag<T> resolvedTag = null;
-
-    OptionalTagEntry(ResourceLocation referent)
-    {
-        super(referent);
-    }
-
-    @Override
-    public boolean resolve(@Nonnull Function<ResourceLocation, Tag<T>> resolver)
-    {
-        if (this.resolvedTag == null)
-        {
-            this.resolvedTag = resolver.apply(this.getSerializedId());
-        }
-        return true; // never fail if resolver returns null
-    }
-
-    @Override
-    public void populate(@Nonnull Collection<T> items)
-    {
-        if (this.resolvedTag != null)
-        {
-            items.addAll(this.resolvedTag.getAllElements());
-        }
+        class TagTarget<U> extends Tag.TagEntry<U> implements IOptionalTagEntry<U>
+        {
+            private Tag<U> resolvedTag = null;
+            protected TagTarget(ResourceLocation referent) {
+                super(referent);
+            }
+
+            @Override
+            public boolean resolve(@Nonnull Function<ResourceLocation, Tag<U>> resolver)
+            {
+                if (this.resolvedTag == null)
+                    this.resolvedTag = resolver.apply(this.getSerializedId());
+                return true; // never fail if resolver returns null
+            }
+
+            @Override
+            public void populate(@Nonnull Collection<U> items)
+            {
+                if (this.resolvedTag != null)
+                    items.addAll(this.resolvedTag.getAllElements());
+            }
+        };
+
+        return ((Tag.Builder<T>)this).add(new TagTarget<>(tag));
     }
 }