From c45f03541ddd2ec94c13f403ba49db5ef960d275 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 16 Jun 2018 16:23:38 -0400
Subject: [PATCH] Ignore Missing Recipes in RecipeBook to avoid data errors

This code was causing NPE's in saving player data, potentially related to reloads.

diff --git a/src/main/java/net/minecraft/server/RecipeBookServer.java b/src/main/java/net/minecraft/server/RecipeBookServer.java
index 1a1619260..c8cdd990e 100644
--- a/src/main/java/net/minecraft/server/RecipeBookServer.java
+++ b/src/main/java/net/minecraft/server/RecipeBookServer.java
@@ -79,6 +79,10 @@ public class RecipeBookServer extends RecipeBook {
         while (iterator.hasNext()) {
             MinecraftKey minecraftkey = (MinecraftKey) iterator.next();
 
+            // Paper start - ignore missing recipes
+            IRecipe recipe = this.h.a(minecraftkey);
+            if (recipe == null) continue;
+            // Paper end
             nbttaglist.add((NBTBase) (new NBTTagString(minecraftkey.toString())));
         }
 
@@ -89,6 +93,10 @@ public class RecipeBookServer extends RecipeBook {
         while (iterator1.hasNext()) {
             MinecraftKey minecraftkey1 = (MinecraftKey) iterator1.next();
 
+            // Paper start - ignore missing recipes
+            IRecipe recipe = this.h.a(minecraftkey1);
+            if (recipe == null) continue;
+            // Paper end
             nbttaglist1.add((NBTBase) (new NBTTagString(minecraftkey1.toString())));
         }
 
-- 
2.19.1