--- a/net/minecraft/commands/arguments/item/ItemInput.java
+++ b/net/minecraft/commands/arguments/item/ItemInput.java
@@ -69,6 +69,6 @@
     }
 
     private String getItemName() {
-        return this.item.unwrapKey().map(ResourceKey::location).orElseGet(() -> "unknown[" + this.item + "]").toString();
+        return this.item.unwrapKey().<Object>map(ResourceKey::location).orElseGet(() -> "unknown[" + this.item + "]").toString();
     }
 }
