Make fields final if possible to ensure immutability

src/main/java/appeng/util/item/OreHelper.java

@@ -11,7 +11,7 @@ import appeng.api.storage.data.IAEItemStack;
 public class OreHelper
 {
 
-	public static OreHelper instance = new OreHelper();
+	public static final OreHelper instance = new OreHelper();
 
 	class ItemRef
 	{
@@ -28,9 +28,9 @@ public class OreHelper
 			hash = ref.hashCode() ^ damage;
 		}
 
-		Item ref;
-		int damage;
-		int hash;
+		final Item ref;
+		final int damage;
+		final int hash;
 
 		@Override
 		public boolean equals(Object obj)
@@ -58,7 +58,7 @@ public class OreHelper
 
 	}
 
-	HashMap<ItemRef, OreResult> references = new HashMap<ItemRef, OreResult>();
+	final HashMap<ItemRef, OreResult> references = new HashMap<ItemRef, OreResult>();
 
 	public OreReference isOre(ItemStack ItemStack)
 	{