only access worldpipenet on server (#2310)

Author: TechLord22

src/main/java/gregtech/api/pipenet/WorldPipeNet.java

@@ -1,5 +1,7 @@
 package gregtech.api.pipenet;
 
+import gregtech.api.util.GTLog;
+
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.nbt.NBTTagList;
 import net.minecraft.util.EnumFacing;
@@ -12,7 +14,11 @@
 import org.jetbrains.annotations.NotNull;
 
 import java.lang.ref.WeakReference;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 public abstract class WorldPipeNet<NodeDataType, T extends PipeNet<NodeDataType>> extends WorldSavedData {
 
@@ -35,9 +41,16 @@ protected void setWorldAndInit(World world) {
         }
     }
 
-    public static String getDataID(final String baseID, final World world) {
-        if (world == null || world.isRemote)
-            throw new RuntimeException("WorldPipeNet should only be created on the server!");
+    public static @NotNull String getDataID(@NotNull final String baseID, @NotNull final World world) {
+        // noinspection ConstantValue
+        if (world == null || world.isRemote) {
+            GTLog.logger.error("WorldPipeNet should only be created on the server!", new Throwable());
+            // noinspection ConstantValue
+            if (world == null) {
+                return baseID;
+            }
+        }
+
         int dimension = world.provider.getDimension();
         return dimension == 0 ? baseID : baseID + '.' + dimension;
     }

src/main/java/gregtech/api/pipenet/tile/TileEntityPipeBase.java

@@ -544,10 +544,12 @@ public boolean shouldRefresh(@NotNull World world, @NotNull BlockPos pos, IBlock
     @Override
     public void onChunkUnload() {
         super.onChunkUnload();
-        WorldPipeNet<?, ?> worldPipeNet = getPipeBlock().getWorldPipeNet(getWorld());
-        PipeNet<?> net = worldPipeNet.getNetFromPos(pos);
-        if (net != null) {
-            net.onChunkUnload();
+        if (!world.isRemote) {
+            WorldPipeNet<?, ?> worldPipeNet = getPipeBlock().getWorldPipeNet(getWorld());
+            PipeNet<?> net = worldPipeNet.getNetFromPos(pos);
+            if (net != null) {
+                net.onChunkUnload();
+            }
         }
     }