fix potential exceptions after world shutdown

core/src/main/java/com/seibel/distanthorizons/core/api/internal/ServerApi.java

@@ -122,7 +122,7 @@ public class ServerApi
 	
 	public void serverPlayerJoinEvent(IServerPlayerWrapper player)
 	{
-		if (DhApiWorldProxy.INSTANCE.worldLoaded() && DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}
@@ -136,7 +136,7 @@ public class ServerApi
 	}
 	public void serverPlayerDisconnectEvent(IServerPlayerWrapper player)
 	{
-		if (DhApiWorldProxy.INSTANCE.worldLoaded() && DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}
@@ -150,7 +150,7 @@ public class ServerApi
 	}
 	public void serverPlayerLevelChangeEvent(IServerPlayerWrapper player, IServerLevelWrapper originLevel, IServerLevelWrapper destinationLevel)
 	{
-		if (DhApiWorldProxy.INSTANCE.worldLoaded() && DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}
@@ -170,7 +170,7 @@ public class ServerApi
 	 */
 	public void pluginMessageReceived(IServerPlayerWrapper player, @NotNull AbstractNetworkMessage message)
 	{
-		if (DhApiWorldProxy.INSTANCE.worldLoaded() && DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}

core/src/main/java/com/seibel/distanthorizons/core/api/internal/SharedApi.java

@@ -211,7 +211,7 @@ public class SharedApi
 		}
 		
 		// ignore updates if the world is read-only
-		if (DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}

core/src/main/java/com/seibel/distanthorizons/core/generation/queues/LodRequestModule.java

@@ -104,7 +104,7 @@ public class LodRequestModule implements Closeable
 		boolean shouldDoWorldGen = this.onWorldGenCompleteListener.shouldDoWorldGen();
 		
 		// if the world is read only don't generate anything
-		shouldDoWorldGen &= !DhApiWorldProxy.INSTANCE.getReadOnly();
+		shouldDoWorldGen &= !DhApiWorldProxy.INSTANCE.tryGetReadOnly();
 		
 		// don't generate chunks for client levels that aren't being rendered
 		// (this can happen when moving between dimensions)

core/src/main/java/com/seibel/distanthorizons/core/generation/queues/WorldGenerationQueue.java

@@ -202,7 +202,7 @@ public class WorldGenerationQueue implements IFullDataSourceRetrievalQueue, IDeb
 	private synchronized void tryQueueNewWorldGenRequestsAsync()
 	{
 		if (!DhApiWorldProxy.INSTANCE.worldLoaded()
-			|| DhApiWorldProxy.INSTANCE.getReadOnly())
+			|| DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return;
 		}

core/src/main/java/com/seibel/distanthorizons/core/multiplayer/client/AbstractFullDataNetworkRequestQueue.java

@@ -151,8 +151,7 @@ public abstract class AbstractFullDataNetworkRequestQueue implements IDebugRende
 	
 	public synchronized boolean tick(DhBlockPos2D targetPos)
 	{
-		if (DhApiWorldProxy.INSTANCE.worldLoaded() 
-			&& DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			return false;
 		}

core/src/main/java/com/seibel/distanthorizons/core/world/AbstractDhWorld.java

@@ -64,7 +64,7 @@ public abstract class AbstractDhWorld implements IDhWorld, Closeable
 		String levelCountStr = F3Screen.NUMBER_FORMAT.format(this.getLoadedLevelCount());
 		
 		String readOnlyStr = "";
-		if (DhApiWorldProxy.INSTANCE.getReadOnly())
+		if (DhApiWorldProxy.INSTANCE.tryGetReadOnly())
 		{
 			readOnlyStr += " - ReadOnly";
 		}

core/src/main/java/com/seibel/distanthorizons/core/world/DhApiWorldProxy.java

@@ -113,6 +113,23 @@ public class DhApiWorldProxy implements IDhApiWorldProxy
 		return this.isReadOnly; 
 	}
 	
+	/** 
+	 * Returns false if no world is loaded.
+	 * Can be used in places where the world state might be a bit more questionable
+	 * without having to worry about the {@link IllegalStateException} thrown by
+	 * {@link DhApiWorldProxy#getReadOnly()}
+	 */
+	public boolean tryGetReadOnly()
+	{
+		if (SharedApi.getAbstractDhWorld() == null)
+		{
+			// no world is loaded, use the default value for the next world
+			return false;
+		}
+		
+		return this.isReadOnly;
+	}
+	
 	
 	
 	//================//