From ecc472a692af5c2df27ef46665b479f210e7133f Mon Sep 17 00:00:00 2001
From: thatsIch <badhard@arcor.de>
Date: Sun, 5 Apr 2015 13:07:19 +0200
Subject: [PATCH] Fixes NPE on random button smashing

---
 .../appeng/items/parts/ItemMultiPart.java     | 27 ++++++++++---------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/main/java/appeng/items/parts/ItemMultiPart.java b/src/main/java/appeng/items/parts/ItemMultiPart.java
index d7cbb3b3d..99a9fe137 100644
--- a/src/main/java/appeng/items/parts/ItemMultiPart.java
+++ b/src/main/java/appeng/items/parts/ItemMultiPart.java
@@ -301,19 +301,22 @@ public class ItemMultiPart extends AEBaseItem implements IPartItem, IItemGroup
 			if( stack.getItem() == this )
 			{
 				PartType pt = this.getTypeByStack( stack );
-				switch( pt )
+				if ( pt != null )
 				{
-					case ImportBus:
-						importBus = true;
-						if( u == pt )
-							group = true;
-						break;
-					case ExportBus:
-						exportBus = true;
-						if( u == pt )
-							group = true;
-						break;
-					default:
+					switch( pt )
+					{
+						case ImportBus:
+							importBus = true;
+							if( u == pt )
+								group = true;
+							break;
+						case ExportBus:
+							exportBus = true;
+							if( u == pt )
+								group = true;
+							break;
+						default:
+					}
 				}
 			}
 		}