From 7ea1e581b7897c4b033014e9ddd4ef09144c7902 Mon Sep 17 00:00:00 2001
From: Raoul Van den Berge <raoulvdberge@gmail.com>
Date: Tue, 23 Aug 2016 20:12:43 +0200
Subject: [PATCH] Fixed Wireless Transmitter crashing when it is transmitting
 to a removed dimension, fixes #285

---
 CHANGELOG.md                                  |  1 +
 .../apiimpl/network/NetworkNodeGraph.java     | 22 +++++++++++--------
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6ba7c82a1..6bed66999 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 - Fixed Grid Filter only updating the Grid when reopening the GUI
 - Fixed Wireless Grid not working cross dimensionally
 - Fixed Grid not displaying items after changing redstone mode
+- Fixed Wireless Transmitter crashing when it is transmitting to a removed dimension
 - Priority field and detector amount field can now display 4 digits at a time
 
 **Features**
diff --git a/src/main/java/refinedstorage/apiimpl/network/NetworkNodeGraph.java b/src/main/java/refinedstorage/apiimpl/network/NetworkNodeGraph.java
index 562c98c35..a5322e772 100755
--- a/src/main/java/refinedstorage/apiimpl/network/NetworkNodeGraph.java
+++ b/src/main/java/refinedstorage/apiimpl/network/NetworkNodeGraph.java
@@ -73,17 +73,21 @@ public class NetworkNodeGraph implements INetworkNodeGraph {
 
                 if (transmitter.canTransmit()) {
                     if (!transmitter.isSameDimension()) {
-                        NetworkNodeGraph dimensionGraph = new NetworkNodeGraph(controller) {
-                            @Override
-                            public World getWorld() {
-                                return DimensionManager.getWorld(transmitter.getReceiverDimension());
-                            }
-                        };
+                        final World dimensionWorld = DimensionManager.getWorld(transmitter.getReceiverDimension());
 
-                        dimensionGraph.rebuild(transmitter.getReceiver(), false);
+                        if (dimensionWorld != null) {
+                            NetworkNodeGraph dimensionGraph = new NetworkNodeGraph(controller) {
+                                @Override
+                                public World getWorld() {
+                                    return dimensionWorld;
+                                }
+                            };
 
-                        newNodes.addAll(dimensionGraph.all());
-                        newNodeHashes.addAll(dimensionGraph.allHashes());
+                            dimensionGraph.rebuild(transmitter.getReceiver(), false);
+
+                            newNodes.addAll(dimensionGraph.all());
+                            newNodeHashes.addAll(dimensionGraph.allHashes());
+                        }
                     } else {
                         BlockPos receiver = transmitter.getReceiver();