commit dd0161021eac54c89c832b5e2c398620d60805df
Author: Leszek Koltunski <leszek@koltunski.pl>
Date:   Tue Nov 2 21:36:58 2021 +0100

    Bugfix.

diff --git a/src/main/java/org/distorted/network/RubikNetwork.java b/src/main/java/org/distorted/network/RubikNetwork.java
index 0cad0712..b6a9e1b0 100644
--- a/src/main/java/org/distorted/network/RubikNetwork.java
+++ b/src/main/java/org/distorted/network/RubikNetwork.java
@@ -156,12 +156,12 @@ public class RubikNetwork implements Runnable
 
     if( len==0 )
       {
-      mReceiver.error("1");
+      if( mReceiver!=null ) mReceiver.error("1");
       return false;
       }
     else if( len<=2 )
       {
-      mReceiver.error(mScores);
+      if( mReceiver!=null ) mReceiver.error(mScores);
       return false;
       }
 
@@ -408,29 +408,29 @@ public class RubikNetwork implements Runnable
         }
       catch( final Exception e)
         {
-        mReceiver.message("Failed to get an answer from the High Scores server");
+        if( mReceiver!=null ) mReceiver.message("Failed to get an answer from the High Scores server");
         return false;
         }
       }
     catch( final UnknownHostException e )
       {
-      mReceiver.message("No access to Internet");
+      if( mReceiver!=null ) mReceiver.message("No access to Internet");
       return false;
       }
     catch( final SecurityException e )
       {
-      mReceiver.message("Application not authorized to connect to the Internet");
+      if( mReceiver!=null ) mReceiver.message("Application not authorized to connect to the Internet");
       return false;
       }
     catch( final Exception e )
       {
-      mReceiver.message(e.getMessage());
+      if( mReceiver!=null ) mReceiver.message(e.getMessage());
       return false;
       }
 
     if( mScores.length()==0 )
       {
-      mReceiver.message("Failed to download scores");
+      if( mReceiver!=null ) mReceiver.message("Failed to download scores");
       return false;
       }