Make command category not null

src/main/java/wtf/beatrice/hidekobot/HidekoBot.java

@@ -131,6 +131,7 @@ public class HidekoBot
         // register message commands
         MessageCommandListener messageCommandListener = new MessageCommandListener();
         messageCommandListener.registerCommand(new HelloCommand());
+        messageCommandListener.registerCommand(new wtf.beatrice.hidekobot.commands.message.AliasCommand());
         messageCommandListener.registerCommand(new wtf.beatrice.hidekobot.commands.message.AvatarCommand());
         messageCommandListener.registerCommand(new wtf.beatrice.hidekobot.commands.message.BotInfoCommand());
         messageCommandListener.registerCommand(new wtf.beatrice.hidekobot.commands.message.CoinFlipCommand());

src/main/java/wtf/beatrice/hidekobot/commands/base/MagicBall.java

@@ -16,7 +16,7 @@ public class MagicBall
 
     public static LinkedList<String> getLabels()
     {
-        return new LinkedList<>(Arrays.asList("8ball", "eightball", "magicball", "8b"));
+        return new LinkedList<>(Arrays.asList("8ball", "8b", "eightball", "magicball"));
     }
 
     private final static List<String> answers = new ArrayList<>(

src/main/java/wtf/beatrice/hidekobot/commands/message/AvatarCommand.java

@@ -5,6 +5,7 @@ import net.dv8tion.jda.api.entities.Mentions;
 import net.dv8tion.jda.api.entities.MessageEmbed;
 import net.dv8tion.jda.api.entities.User;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.HidekoBot;
@@ -35,6 +36,7 @@ public class AvatarCommand  implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.TOOLS;

src/main/java/wtf/beatrice/hidekobot/commands/message/BotInfoCommand.java

@@ -3,6 +3,7 @@ package wtf.beatrice.hidekobot.commands.message;
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.entities.MessageEmbed;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.commands.base.BotInfo;
@@ -32,6 +33,7 @@ public class BotInfoCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.TOOLS;

src/main/java/wtf/beatrice/hidekobot/commands/message/ClearCommand.java

@@ -4,6 +4,7 @@ import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.entities.Message;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import net.dv8tion.jda.api.interactions.components.buttons.Button;
+import org.jetbrains.annotations.NotNull;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.commands.base.ClearChat;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -28,6 +29,7 @@ public class ClearCommand implements MessageCommand
     public boolean passRawArgs() {
         return false;
     }
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.MODERATION;

src/main/java/wtf/beatrice/hidekobot/commands/message/CoinFlipCommand.java

@@ -2,6 +2,7 @@ package wtf.beatrice.hidekobot.commands.message;
 
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.commands.base.CoinFlip;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -30,6 +31,7 @@ public class CoinFlipCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/DiceRollCommand.java

@@ -3,6 +3,7 @@ package wtf.beatrice.hidekobot.commands.message;
 import net.dv8tion.jda.api.EmbedBuilder;
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.objects.Dice;
@@ -29,6 +30,7 @@ public class DiceRollCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/HelloCommand.java

@@ -2,6 +2,7 @@ package wtf.beatrice.hidekobot.commands.message;
 
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
 import wtf.beatrice.hidekobot.objects.commands.MessageCommand;
 
@@ -25,6 +26,7 @@ public class HelloCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/HelpCommand.java

@@ -4,6 +4,7 @@ import net.dv8tion.jda.api.EmbedBuilder;
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import org.apache.commons.text.WordUtils;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.commands.base.Say;
@@ -33,6 +34,7 @@ public class HelpCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.TOOLS;

src/main/java/wtf/beatrice/hidekobot/commands/message/InviteCommand.java

@@ -5,6 +5,7 @@ import net.dv8tion.jda.api.entities.MessageEmbed;
 import net.dv8tion.jda.api.entities.emoji.Emoji;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import net.dv8tion.jda.api.interactions.components.buttons.Button;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.commands.base.Invite;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -33,6 +34,7 @@ public class InviteCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/LoveCalculatorCommand.java

@@ -6,6 +6,7 @@ import net.dv8tion.jda.api.entities.IMentionable;
 import net.dv8tion.jda.api.entities.Mentions;
 import net.dv8tion.jda.api.entities.User;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.Cache;
 import wtf.beatrice.hidekobot.HidekoBot;
@@ -38,6 +39,7 @@ public class LoveCalculatorCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/MagicBallCommand.java

@@ -2,6 +2,7 @@ package wtf.beatrice.hidekobot.commands.message;
 
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.commands.base.MagicBall;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -29,6 +30,7 @@ public class MagicBallCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/commands/message/SayCommand.java

@@ -2,6 +2,7 @@ package wtf.beatrice.hidekobot.commands.message;
 
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import wtf.beatrice.hidekobot.commands.base.Say;
 import wtf.beatrice.hidekobot.objects.commands.CommandCategory;
@@ -29,6 +30,7 @@ public class SayCommand implements MessageCommand
         return true;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.TOOLS;

src/main/java/wtf/beatrice/hidekobot/commands/message/UrbanDictionaryCommand.java

@@ -4,6 +4,7 @@ import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.entities.MessageEmbed;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import net.dv8tion.jda.api.interactions.components.buttons.Button;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
@@ -35,6 +36,7 @@ public class UrbanDictionaryCommand implements MessageCommand
         return false;
     }
 
+    @NotNull
     @Override
     public CommandCategory getCategory() {
         return CommandCategory.FUN;

src/main/java/wtf/beatrice/hidekobot/objects/commands/MessageCommand.java

@@ -2,6 +2,7 @@ package wtf.beatrice.hidekobot.objects.commands;
 
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.LinkedList;
@@ -44,6 +45,7 @@ public interface MessageCommand
      *
      * @return the command category.
      */
+    @NotNull
     CommandCategory getCategory();
 
     /**