Split holder implementation

api/src/main/java/com/viaversion/viaversion/api/minecraft/Holder.java

@@ -35,7 +35,7 @@ public interface Holder<T> {
      * @throws IllegalArgumentException if the id is negative
      */
     static <T> Holder<T> of(final int id) {
-        return new HolderImpl<>(id);
+        return new IdHolder<>(id);
     }
 
     /**
@@ -46,7 +46,7 @@ public interface Holder<T> {
      * @return a new direct holder
      */
     static <T> Holder<T> of(final T value) {
-        return new HolderImpl<>(value);
+        return new ValueHolder<>(value);
     }
 
     /**

api/src/main/java/com/viaversion/viaversion/api/minecraft/IdHolder.java

@@ -25,49 +25,29 @@ package com.viaversion.viaversion.api.minecraft;
 import com.google.common.base.Preconditions;
 import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 
-final class HolderImpl<T> implements Holder<T> {
+record IdHolder<T>(int id) implements Holder<T> {
 
-    private final T value;
+    IdHolder {
-    private final int id;
-
-    HolderImpl(final int id) {
         Preconditions.checkArgument(id >= 0, "id cannot be negative");
-        this.value = null;
-        this.id = id;
-    }
-
-    HolderImpl(final T value) {
-        this.value = value;
-        this.id = -1;
     }
 
     @Override
     public boolean isDirect() {
-        return id == -1;
+        return false;
     }
 
     @Override
     public boolean hasId() {
-        return id != -1;
+        return true;
     }
 
     @Override
     public T value() {
-        Preconditions.checkArgument(isDirect(), "Holder is not direct");
+        throw new IllegalArgumentException("Holder is not direct");
-        return value;
-    }
-
-    @Override
-    public int id() {
-        return id;
     }
 
     @Override
     public Holder<T> updateId(final Int2IntFunction rewriteFunction) {
-        if (isDirect()) {
-            return this;
-        }
-
         final int rewrittenId = rewriteFunction.applyAsInt(id);
         if (rewrittenId == id) {
             return this;
@@ -77,12 +57,4 @@ final class HolderImpl<T> implements Holder<T> {
         }
         return Holder.of(rewrittenId);
     }
-
-    @Override
-    public String toString() {
-        return "HolderImpl{" +
-            "value=" + value +
-            ", id=" + id +
-            '}';
-    }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/ValueHolder.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.minecraft;
+
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
+
+record ValueHolder<T>(T value) implements Holder<T> {
+
+    @Override
+    public boolean isDirect() {
+        return true;
+    }
+
+    @Override
+    public boolean hasId() {
+        return false;
+    }
+
+    @Override
+    public int id() {
+        return -1;
+    }
+
+    @Override
+    public Holder<T> updateId(final Int2IntFunction rewriteFunction) {
+        return this;
+    }
+}