From 129fb75e4cf1a3e2ad7e55a8bc36234cbd220d79 Mon Sep 17 00:00:00 2001
From: Bernhard Bonigl <bernhard.bonigl@gmail.com>
Date: Sat, 2 May 2015 13:41:51 +0200
Subject: [PATCH] Fix drain-comparator NPE when the controller gets broken
 #1586

---
 .../java/tconstruct/smeltery/logic/SmelteryDrainLogic.java   | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/main/java/tconstruct/smeltery/logic/SmelteryDrainLogic.java b/src/main/java/tconstruct/smeltery/logic/SmelteryDrainLogic.java
index a3f46bff353..ed5edd726e6 100644
--- a/src/main/java/tconstruct/smeltery/logic/SmelteryDrainLogic.java
+++ b/src/main/java/tconstruct/smeltery/logic/SmelteryDrainLogic.java
@@ -190,6 +190,11 @@ public int comparatorStrength ()
         if(master == null)
             return 0;
         SmelteryLogic smeltery = (SmelteryLogic) worldObj.getTileEntity(master.x, master.y, master.z);
+
+        // this can happen when the comparator checks its strength before the drain is getting updated on a broken master (smeltery controller)
+        if(smeltery == null)
+            return 0;
+
         if(smeltery.maxLiquid == 0)
             return 0;
         return 15 * smeltery.currentLiquid / smeltery.maxLiquid;