Add multilingual support

Add multilingual support

src/main/java/emu/grasscutter/Config.java

@@ -21,6 +21,7 @@ public final class Config {
 	public ServerRunMode RunMode = ServerRunMode.HYBRID; // HYBRID, DISPATCH_ONLY, GAME_ONLY
 	public GameServerOptions GameServer = new GameServerOptions();
 	public DispatchServerOptions DispatchServer = new DispatchServerOptions();
+	public String Language = "en_us";
 
 	public GameServerOptions getGameServerOptions() {
 		return GameServer;

src/main/java/emu/grasscutter/Grasscutter.java

@@ -30,6 +30,7 @@ import emu.grasscutter.utils.Crypto;
 public final class Grasscutter {
 	private static final Logger log = (Logger) LoggerFactory.getLogger(Grasscutter.class);
 	private static Config config;
+	private static Language language;
 	
 	private static final Gson gson = new GsonBuilder().setPrettyPrinting().create();
 	private static final File configFile = new File("./config.json");
@@ -48,6 +49,9 @@ public final class Grasscutter {
 		
 		// Load server configuration.
 		Grasscutter.loadConfig();
+
+		// Load Language
+		Grasscutter.loadLanguage();
 		
 		// Check server structure.
 		Utils.startupCheck();
@@ -68,7 +72,7 @@ public final class Grasscutter {
 		}
 		
 		// Initialize server.
-		Grasscutter.getLogger().info("Starting Grasscutter...");
+		Grasscutter.getLogger().info(language.Starting_Grasscutter);
 		
 		// Load all resources.
 		Grasscutter.updateDayOfWeek();
@@ -96,9 +100,9 @@ public final class Grasscutter {
 		} else if (getConfig().RunMode == ServerRunMode.GAME_ONLY) {
 			gameServer.start();
 		} else {
-			getLogger().error("Invalid server run mode. " + getConfig().RunMode);
-			getLogger().error("Server run mode must be 'HYBRID', 'DISPATCH_ONLY', or 'GAME_ONLY'. Unable to start Grasscutter...");
-			getLogger().error("Shutting down...");
+			getLogger().error(language.Invalid_server_run_mode + " " + getConfig().RunMode);
+			getLogger().error(language.Server_run_mode);
+			getLogger().error(language.Shutting_down);
 			System.exit(1);
 		}
 		
@@ -128,6 +132,31 @@ public final class Grasscutter {
 			saveConfig();
 		}
 	}
+
+	public static void loadLanguage() {
+		try (FileReader file = new FileReader(String.format("./language/%s.json", Grasscutter.config.Language))) {
+			language = gson.fromJson(file, Language.class);
+		} catch (Exception e) {
+			Grasscutter.language = new Language();
+			Grasscutter.config.Language = "en_us";
+			saveConfig();
+
+			try {
+				File folder = new File("./language");
+				if (!folder.exists() && !folder.isDirectory()) {
+					//noinspection ResultOfMethodCallIgnored
+					folder.mkdirs();
+				}
+			} catch (Exception ee) {
+				Grasscutter.getLogger().error("Unable to create language folder.");
+			}
+			try (FileWriter file = new FileWriter("./language/en_us.json")) {
+				file.write(gson.toJson(language));
+			} catch (Exception ee) {
+				Grasscutter.getLogger().error("Unable to create language file.");
+			}
+		}
+	}
 	
 	public static void saveConfig() {
 		try (FileWriter file = new FileWriter(configFile)) {
@@ -139,22 +168,22 @@ public final class Grasscutter {
 	
 	public static void startConsole() {
 		String input;
-		getLogger().info("Done! For help, type \"help\"");
+		getLogger().info(language.Start_done);
 		try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
 			while ((input = br.readLine()) != null) {
 				try {
 					if (getConfig().RunMode == ServerRunMode.DISPATCH_ONLY) {
-						getLogger().error("Commands are not supported in dispatch only mode.");
+						getLogger().error(language.Dispatch_mode_not_support_command);
 						return;
 					}
 					
 					CommandMap.getInstance().invoke(null, input);
 				} catch (Exception e) {
-					Grasscutter.getLogger().error("Command error:", e);
+					Grasscutter.getLogger().error(language.Command_error, e);
 				}
 			}
 		} catch (Exception e) {
-			Grasscutter.getLogger().error("An error occurred.", e);
+			Grasscutter.getLogger().error(language.error, e);
 		}
 	}
 
@@ -162,6 +191,10 @@ public final class Grasscutter {
 		return config;
 	}
 
+	public static Language getLanguage() {
+		return language;
+	}
+
 	public static Logger getLogger() {
 		return log;
 	}

src/main/java/emu/grasscutter/Language.java

+package emu.grasscutter;
+
+public final class Language {
+    public String An_error_occurred_during_game_update = "An error occurred during game update.";
+    public String Starting_Grasscutter = "Starting Grasscutter...";
+    public String Invalid_server_run_mode = "Invalid server run mode.";
+    public String Server_run_mode = "Server run mode must be 'HYBRID', 'DISPATCH_ONLY', or 'GAME_ONLY'. Unable to start Grasscutter...";
+    public String Shutting_down = "Shutting down...";
+    public String Start_done = "Done! For help, type \"help\"";
+    public String Dispatch_mode_not_support_command = "Commands are not supported in dispatch only mode.";
+    public String Command_error = "Command error:";
+    public String error = "An error occurred.";
+    public String grasscutter_is_free = "Grasscutter is FREE software. If you have paid for this, you may have been scammed. Homepage: https://github.com/Grasscutters/Grasscutter";
+    public String Game_start_port = "Game Server started on port %s";
+    public String Client_connect = "Client connected from %s";
+    public String Client_disconnect = "Client disconnected from %s";
+    public String Client_request = "[Dispatch] Client %s %s request: %s";
+    public String Not_load_keystore = "[Dispatch] Unable to load keystore. Trying default keystore password...";
+    public String Use_default_keystore = "[Dispatch] The default keystore password was loaded successfully. Please consider setting the password to 123456 in config.json.";
+    public String Load_keystore_error = "[Dispatch] Error while loading keystore!";
+    public String Not_find_ssl_cert = "[Dispatch] No SSL cert found! Falling back to HTTP server.";
+    public String Welcome = "Welcome to Grasscutter";
+    public String Potential_unhandled_request = "[Dispatch] Potential unhandled %s request: %s";
+    public String Client_login_token = "[Dispatch] Client %s is trying to log in via token";
+    public String Client_token_login_failed = "[Dispatch] Client %s failed to log in via token";
+    public String Client_login_in_token = "[Dispatch] Client %s logged in via token as %s";
+    public String Game_account_cache_error = "Game account cache information error";
+    public String Wrong_session_key = "Wrong session key.";
+    public String Client_exchange_combo_token = "[Dispatch] Client %s succeed to exchange combo token";
+    public String Client_failed_exchange_combo_token = "[Dispatch] Client %s failed to exchange combo token";
+    public String Dispatch_start_server_port = "[Dispatch] Dispatch server started on port %s";
+    public String Client_failed_login_account_create = "[Dispatch] Client %s failed to log in: Account %s created";
+    public String Client_failed_login_account_create_failed = "[Dispatch] Client %s failed to log in: Account create failed";
+    public String Client_failed_login_account_no_found = "[Dispatch] Client %s failed to log in: Account no found";
+    public String Client_login = "[Dispatch] Client %s logged in as %s";
+    public String Username_not_found = "Username not found.";
+    public String Username_not_found_create_failed = "Username not found, create failed.";
+
+    // Command
+    public String No_command_specified = "No command specified.";
+    public String Unknown_command = "Unknown command: ";
+    public String You_not_permission_run_command = "You do not have permission to run this command.";
+    public String This_command_can_only_run_from_console = "This command can only be run from the console.";
+    public String Run_this_command_in_game = "Run this command in-game.";
+    public String Invalid_playerId = "Invalid playerId.";
+    public String Player_not_found = "Player not found.";
+    public String Player_is_offline = "Player is offline.";
+    public String Invalid_item_id = "Invalid item id.";
+    public String Invalid_item_or_player_id = "Invalid item or player ID.";
+    public String Enabled = "enabled";
+    public String Disabled = "disabled";
+    public String No_command_found = "No command found.";
+    public String Help = "Help";
+    public String Player_not_found_or_offline = "Player not found or offline.";
+    public String Invalid_arguments = "Invalid arguments.";
+    public String Success = "Success";
+    public String Invalid_entity_id = "Invalid entity id.";
+
+    // Help
+    public String Help_usage = "   Usage: ";
+    public String Help_aliases = "   Aliases: ";
+    public String Help_available_command = "Available commands:";
+
+    // Account
+    public String Modify_user_account = "Modify user accounts";
+    public String Invalid_UID = "Invalid UID.";
+    public String Account_exists = "Account already exists.";
+    public String Account_create_UID = "Account created with UID %s.";
+    public String Account_delete = "Account deleted.";
+    public String Account_not_find = "Account not found.";
+    public String Account_command_usage = "Usage: account <create|delete> <username> [uid]";
+
+    // Broadcast
+    public String Broadcast_command_usage = "Usage: broadcast <message>";
+    public String Broadcast_message_sent = "Message sent.";
+
+    // ChangeScene
+    public String Change_screen_usage = "Usage: changescene <scene id>";
+    public String Change_screen_you_in_that_screen = "You are already in that scene";
+    public String Change_screen = "Changed to scene ";
+    public String Change_screen_not_exist = "Scene does not exist";
+
+    // Clear
+    public String Clear_weapons = "Cleared weapons for %s .";
+    public String Clear_artifacts = "Cleared artifacts for %s .";
+    public String Clear_materials = "Cleared materials for %s .";
+    public String Clear_furniture = "Cleared furniture for %s .";
+    public String Clear_displays = "Cleared displays for %s .";
+    public String Clear_virtuals = "Cleared virtuals for %s .";
+    public String Clear_everything = "Cleared everything for %s .";
+
+    // Coop
+    public String Coop_usage = "Usage: coop <playerId> <target playerId>";
+
+    // Drop
+    public String Drop_usage = "Usage: drop <itemId|itemName> [amount]";
+    public String Drop_dropped_of = "Dropped %s of %s.";
+
+    // EnterDungeon
+    public String EnterDungeon_usage = "Usage: enterdungeon <dungeon id>";
+    public String EnterDungeon_changed_to_dungeon = "Changed to dungeon ";
+    public String EnterDungeon_dungeon_not_found = "Dungeon does not exist";
+    public String EnterDungeon_you_in_that_dungeon = "You are already in that dungeon";
+
+    // GiveAll
+    public String GiveAll_usage = "Usage: giveall [player] [amount]";
+    public String GiveAll_item = "Giving all items...";
+    public String GiveAll_done = "Giving all items done";
+    public String GiveAll_invalid_amount_or_playerId = "Invalid amount or player ID.";
+
+    // GiveArtifact
+    public String GiveArtifact_usage = "Usage: giveart|gart [player] <artifactId> <mainPropId> [<appendPropId>[,<times>]]... [level]";
+    public String GiveArtifact_invalid_artifact_id = "Invalid artifact ID.";
+    public String GiveArtifact_given = "Given %s to %s.";
+
+    // GiveChar
+    public String GiveChar_usage = "Usage: givechar <player> <itemId|itemName> [amount]";
+    public String GiveChar_given = "Given %s with level %s to %s.";
+    public String GiveChar_invalid_avatar_id = "Invalid avatar id.";
+    public String GiveChar_invalid_avatar_level = "Invalid avatar level.";
+    public String GiveChar_invalid_avatar_or_player_id = "Invalid avatar or player ID.";
+
+    // Give
+    public String Give_usage = "Usage: give <player> <itemId|itemName> [amount] [level]";
+    public String Give_refinement_only_applicable_weapons = "Refinement is only applicable to weapons.";
+    public String Give_refinement_must_between_1_and_5 = "Refinement must be between 1 and 5.";
+    public String Give_given = "Given %s of %s to %s.";
+    public String Give_given_with_level_and_refinement = "Given %s with level %s, refinement %s %s times to %s";
+    public String Give_given_level = "Given %s with level %s %s times to %s";
+
+    // GodMode
+    public String Godmode_status = "Godmode is now %s for %s .";
+
+    // Heal
+    public String Heal_message = "All characters have been healed.";
+
+    // Kick
+    public String Kick_player_kick_player = "Player [%s:%s] has kicked player [%s:%s]";
+    public String Kick_server_player = "Kicking player [%s:%s]";
+
+    // Kill
+    public String Kill_usage = "Usage: killall [playerUid] [sceneId]";
+    public String Kill_scene_not_found_in_player_world = "Scene not found in player world";
+    public String Kill_kill_monsters_in_scene = "Killing %s monsters in scene %s";
+
+    // KillCharacter
+    public String KillCharacter_usage = "Usage: /killcharacter [playerId]";
+    public String KillCharacter_kill_current_character = "Killed %s current character.";
+
+    // List
+    public String List_message = "There are %s player(s) online:";
+
+    // Permission
+    public String Permission_usage = "Usage: permission <add|remove> <username> <permission>";
+    public String Permission_add = "Permission added.";
+    public String Permission_have_permission = "They already have this permission!";
+    public String Permission_remove = "Permission removed.";
+    public String Permission_not_have_permission = "They don't have this permission!";
+
+    // Position
+    public String Position_message = "Coord: %.3f, %.3f, %.3f\nScene id: %d";
+
+    // Reload
+    public String Reload_reload_start = "Reloading config.";
+    public String Reload_reload_done = "Reload complete.";
+
+    // ResetConst
+    public String ResetConst_reset_all = "Reset all avatars' constellations.";
+    public String ResetConst_reset_all_done = "Constellations for %s have been reset. Please relog to see changes.";
+
+    // ResetShopLimit
+    public String ResetShopLimit_usage = "Usage: /resetshop <player id>";
+
+    // SendMail
+    public String SendMail_usage = "Usage: give [player] <itemId|itemName> [amount]";
+    public String SendMail_user_not_exist = "The user with an id of '%s' does not exist";
+    public String SendMail_start_composition = "Starting composition of message.\nPlease use `/sendmail <title>` to continue.\nYou can use `/sendmail stop` at any time";
+    public String SendMail_templates = "Mail templates coming soon implemented...";
+    public String SendMail_invalid_arguments = "Invalid arguments.\nUsage `/sendmail <userId|all|help> [templateId]`";
+    public String SendMail_send_cancel = "Message sending cancelled";
+    public String SendMail_send_done = "Message sent to user %s!";
+    public String SendMail_send_all_done = "Message sent to all users!";
+    public String SendMail_not_composition_end = "Message composition not at final stage.\nPlease use `/sendmail %s` or `/sendmail stop` to cancel";
+    public String SendMail_Please_use = "Please use `/sendmail %s`";
+    public String SendMail_set_title = "Message title set as '%s'.\nUse '/sendmail <content>' to continue.";
+    public String SendMail_set_contents = "Message contents set as '%s'.\nUse '/sendmail <sender>' to continue.";
+    public String SendMail_set_message_sender = "Message sender set as '%s'.\nUse '/sendmail <itemId|itemName|finish> [amount] [level]' to continue.";
+    public String SendMail_send = "Attached %s of %s (level %s) to the message.\nContinue adding more items or use `/sendmail finish` to send the message.";
+    public String SendMail_invalid_arguments_please_use = "Invalid arguments \n Please use `/sendmail %s`";
+    public String SendMail_title = "<title>";
+    public String SendMail_message = "<message>";
+    public String SendMail_sender = "<sender>";
+    public String SendMail_arguments = "<itemId|itemName|finish> [amount] [level]";
+    public String SendMail_error = "ERROR: invalid construction stage %s. Check console for stacktrace.";
+
+    // SendMessage
+    public String SendMessage_usage = "Usage: sendmessage <player> <message>";
+    public String SenaMessage_message_sent = "Message sent.";
+
+    // SetFetterLevel
+    public String SetFetterLevel_usage = "Usage: setfetterlevel <level>";
+    public String SetFetterLevel_fetter_level_must_between_0_and_10 = "Fetter level must be between 0 and 10.";
+    public String SetFetterLevel_fetter_set_level = "Fetter level set to %s";
+    public String SetFetterLevel_invalid_fetter_level = "Invalid fetter level.";
+
+    // SetStats
+    public String SetStats_usage = "Usage: setstats|stats <stat> <value>";
+    public String SetStats_setstats_help_message = "Usage: /setstats|stats <hp | mhp | def | atk | em | er | crate | cdmg> <value> for basic stats";
+    public String SetStats_stats_help_message = "Usage: /stats <epyro | ecryo | ehydro | egeo | edend | eelec | ephys> <amount> for elemental bonus";
+    public String SetStats_set_max_hp = "MAX HP set to %s.";
+    public String SetStats_set_max_hp_error = "Invalid Max HP value.";
+    public String SetStats_set_hp = "HP set to %s.";
+    public String SetStats_set_hp_error = "Invalid HP value.";
+    public String SetStats_set_def = "DEF set to %s.";
+    public String SetStats_set_def_error = "Invalid DEF value.";
+    public String SetStats_set_atk = "ATK set to %s.";
+    public String SetStats_set_atk_error = "Invalid ATK value.";
+    public String SetStats_set_em = "Elemental Mastery set to %s.";
+    public String SetStats_set_em_error = "Invalid EM value.";
+    public String SetStats_set_er = "Energy recharge set to %s%.";
+    public String SetStats_set_er_error = "Invalid ER value.";
+    public String SetStats_set_cr = "Crit Rate set to %s%.";
+    public String SetStats_set_cr_error = "Invalid Crit Rate value.";
+    public String SetStats_set_cd = "Crit DMG set to %s%.";
+    public String SetStats_set_cd_error = "Invalid Crit DMG value.";
+    public String SetStats_set_pdb = "Pyro DMG Bonus set to %s%.";
+    public String SetStats_set_pdb_error = "Invalid Pyro DMG Bonus value.";
+    public String SetStats_set_cdb = "Cyro DMG Bonus set to %s%.";
+    public String SetStats_set_cdb_error = "Invalid Cyro DMG Bonus value.";
+    public String SetStats_set_hdb = "Hydro DMG Bonus set to %s%.";
+    public String SetStats_set_hdb_error = "Invalid Hydro DMG Bonus value.";
+    public String SetStats_set_adb = "Anemo DMG Bonus set to %s%.";
+    public String SetStats_set_adb_error = "Invalid Anemo DMG Bonus value.";
+    public String SetStats_set_gdb = "Geo DMG Bonus set to %s%.";
+    public String SetStats_set_gdb_error = "Invalid Geo DMG Bonus value.";
+    public String SetStats_set_edb = "Electro DMG Bonus set to %s%.";
+    public String SetStats_set_edb_error = "Invalid Electro DMG Bonus value.";
+    public String SetStats_set_physdb = "Physical DMG Bonus set to %s%.";
+    public String SetStats_set_physdb_error = "Invalid Physical DMG Bonus value.";
+    public String SetStats_set_ddb = "Dendro DMG Bonus set to %s%.";
+    public String SetStats_set_ddb_error = "Invalid Dendro DMG Bonus value.";
+
+    // SetWorldLevel
+    public String SetWorldLevel_usage = "Usage: setworldlevel <level>";
+    public String SetWorldLevel_world_level_must_between_0_and_8 = "World level must be between 0-8";
+    public String SetWorldLevel_set_world_level = "World level set to %s.";
+    public String SetWorldLevel_invalid_world_level = "Invalid world level.";
+
+    // Spawn
+    public String Spawn_usage = "Usage: spawn <entityId> [amount] [level(monster only)]";
+    public String Spawn_message = "Spawned %s of %s.";
+
+    // Stop
+    public String Stop_message = "Server shutting down...";
+
+    // Talent
+    public String Talent_usage_1 = "To set talent level: /talent set <talentID> <value>";
+    public String Talent_usage_2 = "Another way to set talent level: /talent <n or e or q> <value>";
+    public String Talent_usage_3 = "To get talent ID: /talent getid";
+    public String Talent_lower_16 = "Invalid talent level. Level should be lower than 16";
+    public String Talent_set_atk = "Set talent Normal ATK to %s.";
+    public String Talent_set_e = "Set talent E to %s.";
+    public String Talent_set_q = "Set talent Q to %s.";
+    public String Talent_invalid_skill_id = "Invalid skill ID.";
+    public String Talent_set_this = "Set this talent to %s.";
+    public String Talent_invalid_talent_level = "Invalid talent level.";
+    public String Talent_normal_attack_id = "Normal Attack ID %s.";
+    public String Talent_e_skill_id = "E skill ID %s.";
+    public String Talent_q_skill_id = "Q skill ID %s.";
+
+    // TeleportAll
+    public String TeleportAll_message = "You only can use this command in MP mode.";
+
+    // Teleport
+    public String Teleport_usage_server = "Usage: /tp @<player id> <x> <y> <z> [scene id]";
+    public String Teleport_usage = "Usage: /tp [@<player id>] <x> <y> <z> [scene id]";
+    public String Teleport_specify_player_id = "You must specify a player id.";
+    public String Teleport_invalid_position = "Invalid position.";
+    public String Teleport_message = "Teleported %s to %s,%s,%s in scene %s";
+
+    // Weather
+    public String Weather_usage = "Usage: weather <weatherId> [climateId]";
+    public String Weather_message = "Changed weather to %s with climate %s";
+    public String Weather_invalid_id = "Invalid ID.";
+}

src/main/java/emu/grasscutter/command/CommandMap.java

@@ -107,7 +107,7 @@ public final class CommandMap {
     public void invoke(Player player, String rawMessage) {
         rawMessage = rawMessage.trim();
         if (rawMessage.length() == 0) {
-            CommandHandler.sendMessage(player, "No command specified.");
+            CommandHandler.sendMessage(player, Grasscutter.getLanguage().No_command_specified);
             return;
         }
 
@@ -122,7 +122,7 @@ public final class CommandMap {
         // Get command handler.
         CommandHandler handler = this.commands.get(label);
         if (handler == null) {
-            CommandHandler.sendMessage(player, "Unknown command: " + label);
+            CommandHandler.sendMessage(player, Grasscutter.getLanguage().Unknown_command + label);
             return;
         }
 
@@ -131,7 +131,7 @@ public final class CommandMap {
             String permissionNode = this.annotations.get(label).permission();
             Account account = player.getAccount();
             if (!permissionNode.isEmpty() && !account.hasPermission(permissionNode)) {
-                CommandHandler.sendMessage(player, "You do not have permission to run this command.");
+                CommandHandler.sendMessage(player, Grasscutter.getLanguage().You_not_permission_run_command);
                 return;
             }
         }

src/main/java/emu/grasscutter/command/commands/AccountCommand.java

@@ -14,12 +14,12 @@ public final class AccountCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender != null) {
-            CommandHandler.sendMessage(sender, "This command can only be run from the console.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().This_command_can_only_run_from_console);
             return;
         }
 
         if (args.size() < 2) {
-            CommandHandler.sendMessage(null, "Usage: account <create|delete> <username> [uid]");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Account_command_usage);
             return;
         }
 
@@ -28,7 +28,7 @@ public final class AccountCommand implements CommandHandler {
 
         switch (action) {
             default:
-                CommandHandler.sendMessage(null, "Usage: account <create|delete> <username> [uid]");
+                CommandHandler.sendMessage(null, Grasscutter.getLanguage().Account_command_usage);
                 return;
             case "create":
                 int uid = 0;
@@ -36,27 +36,27 @@ public final class AccountCommand implements CommandHandler {
                     try {
                         uid = Integer.parseInt(args.get(2));
                     } catch (NumberFormatException ignored) {
-                        CommandHandler.sendMessage(null, "Invalid UID.");
+                        CommandHandler.sendMessage(null, Grasscutter.getLanguage().Invalid_UID);
                         return;
                     }
                 }
 
                 emu.grasscutter.game.Account account = DatabaseHelper.createAccountWithId(username, uid);
                 if (account == null) {
-                    CommandHandler.sendMessage(null, "Account already exists.");
+                    CommandHandler.sendMessage(null, Grasscutter.getLanguage().Account_exists);
                     return;
                 } else {
                     account.addPermission("*");
                     account.save(); // Save account to database.
 
-                    CommandHandler.sendMessage(null, "Account created with UID " + account.getPlayerUid() + ".");
+                    CommandHandler.sendMessage(null, String.format(Grasscutter.getLanguage().Account_create_UID, account.getPlayerUid()));
                 }
                 return;
             case "delete":
                 if (DatabaseHelper.deleteAccount(username)) {
-                    CommandHandler.sendMessage(null, "Account deleted.");
+                    CommandHandler.sendMessage(null, Grasscutter.getLanguage().Account_delete);
                 } else {
-                    CommandHandler.sendMessage(null, "Account not found.");
+                    CommandHandler.sendMessage(null, Grasscutter.getLanguage().Account_not_find);
                 }
         }
     }

src/main/java/emu/grasscutter/command/commands/BroadcastCommand.java

@@ -14,7 +14,7 @@ public final class BroadcastCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (args.size() < 1) {
-            CommandHandler.sendMessage(sender, "Usage: broadcast <message>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Broadcast_command_usage);
             return;
         }
 
@@ -24,6 +24,6 @@ public final class BroadcastCommand implements CommandHandler {
             CommandHandler.sendMessage(p, message);
         }
 
-        CommandHandler.sendMessage(sender, "Message sent.");
+        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Broadcast_message_sent);
     }
 }

src/main/java/emu/grasscutter/command/commands/ChangeSceneCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
+import emu.grasscutter.game.gacha.GachaRecord;
 import emu.grasscutter.game.player.Player;
 
 import java.util.List;
@@ -12,12 +14,12 @@ public final class ChangeSceneCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return;
         }
 
         if (args.size() < 1) {
-            CommandHandler.sendMessage(sender, "Usage: changescene <scene id>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Change_screen_usage);
             return;
         }
 
@@ -25,18 +27,18 @@ public final class ChangeSceneCommand implements CommandHandler {
             int sceneId = Integer.parseInt(args.get(0));
             
             if (sceneId == sender.getSceneId()) {
-            	CommandHandler.sendMessage(sender, "You are already in that scene");
+            	CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Change_screen_you_in_that_screen);
             	return;
             }
             
             boolean result = sender.getWorld().transferPlayerToScene(sender, sceneId, sender.getPos());
-            CommandHandler.sendMessage(sender, "Changed to scene " + sceneId);
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Change_screen + sceneId);
             
             if (!result) {
-                CommandHandler.sendMessage(sender, "Scene does not exist");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Change_screen_not_exist);
             }
         } catch (Exception e) {
-            CommandHandler.sendMessage(sender, "Usage: changescene <scene id>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Change_screen_usage);
         }
     }
 }

src/main/java/emu/grasscutter/command/commands/ClearCommand.java

@@ -20,7 +20,7 @@ public final class ClearCommand implements CommandHandler {
         int target;
         String cmdSwitch = "";
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return;
         }
         Inventory playerInventory = sender.getInventory();
@@ -39,7 +39,7 @@ public final class ClearCommand implements CommandHandler {
                             .filter(item -> item.getItemType() == ItemType.ITEM_WEAPON)
                             .filter(item -> !item.isLocked() && !item.isEquipped())
                             .forEach(item -> playerInventory.removeItem(item, item.getCount()));
-                    sender.dropMessage("Cleared weapons for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_weapons, targetPlayer.getNickname()));
                 }
                 case "art" -> {
                     playerInventory.getItems().values().stream()
@@ -47,7 +47,7 @@ public final class ClearCommand implements CommandHandler {
                             .filter(item -> item.getLevel() == 1 && item.getExp() == 0)
                             .filter(item -> !item.isLocked() && !item.isEquipped())
                             .forEach(item -> playerInventory.removeItem(item, item.getCount()));
-                    sender.dropMessage("Cleared artifacts for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_artifacts, targetPlayer.getNickname()));
                 }
                 case "mat" -> {
                     playerInventory.getItems().values().stream()
@@ -55,7 +55,7 @@ public final class ClearCommand implements CommandHandler {
                             .filter(item -> item.getLevel() == 1 && item.getExp() == 0)
                             .filter(item -> !item.isLocked() && !item.isEquipped())
                             .forEach(item -> playerInventory.removeItem(item, item.getCount()));
-                    sender.dropMessage("Cleared artifacts for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_artifacts, targetPlayer.getNickname()));
                 }
                 case "all" -> {
                     playerInventory.getItems().values().stream()
@@ -63,45 +63,45 @@ public final class ClearCommand implements CommandHandler {
                             .filter(item1 -> item1.getLevel() == 1 && item1.getExp() == 0)
                             .filter(item1 -> !item1.isLocked() && !item1.isEquipped())
                             .forEach(item1 -> playerInventory.removeItem(item1, item1.getCount()));
-                    sender.dropMessage("Cleared artifacts for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_artifacts, targetPlayer.getNickname()));
                     playerInventory.getItems().values().stream()
                             .filter(item2 -> item2.getItemType() == ItemType.ITEM_MATERIAL)
                             .filter(item2 -> !item2.isLocked() && !item2.isEquipped())
                             .forEach(item2 -> playerInventory.removeItem(item2, item2.getCount()));
-                    sender.dropMessage("Cleared materials for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_materials, targetPlayer.getNickname()));
                     playerInventory.getItems().values().stream()
                             .filter(item3 -> item3.getItemType() == ItemType.ITEM_WEAPON)
                             .filter(item3 -> item3.getLevel() == 1 && item3.getExp() == 0)
                             .filter(item3 -> !item3.isLocked() && !item3.isEquipped())
                             .forEach(item3 -> playerInventory.removeItem(item3, item3.getCount()));
-                    sender.dropMessage("Cleared weapons for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_artifacts, targetPlayer.getNickname()));
                     playerInventory.getItems().values().stream()
                             .filter(item4 -> item4.getItemType() == ItemType.ITEM_FURNITURE)
                             .filter(item4 -> !item4.isLocked() && !item4.isEquipped())
                             .forEach(item4 -> playerInventory.removeItem(item4, item4.getCount()));
-                    sender.dropMessage("Cleared furniture for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_furniture, targetPlayer.getNickname()));
                     playerInventory.getItems().values().stream()
                             .filter(item5 -> item5.getItemType() == ItemType.ITEM_DISPLAY)
                             .filter(item5 -> !item5.isLocked() && !item5.isEquipped())
                             .forEach(item5 -> playerInventory.removeItem(item5, item5.getCount()));
-                    sender.dropMessage("Cleared displays for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_displays, targetPlayer.getNickname()));
                     playerInventory.getItems().values().stream()
                             .filter(item6 -> item6.getItemType() == ItemType.ITEM_VIRTUAL)
                             .filter(item6 -> !item6.isLocked() && !item6.isEquipped())
                             .forEach(item6 -> playerInventory.removeItem(item6, item6.getCount()));
-                    sender.dropMessage("Cleared virtuals for " + targetPlayer.getNickname() + " .");
-                    sender.dropMessage("Cleared everything for " + targetPlayer.getNickname() + " .");
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_virtuals, targetPlayer.getNickname()));
+                    sender.dropMessage(String.format(Grasscutter.getLanguage().Clear_everything, targetPlayer.getNickname()));
                 }
             }
         } catch (NumberFormatException ignored) {
             // TODO: Parse from item name using GM Handbook.
-            CommandHandler.sendMessage(sender, "Invalid playerId.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
             return;
         }
 
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
     }

src/main/java/emu/grasscutter/command/commands/CoopCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
 import emu.grasscutter.game.player.Player;
@@ -12,7 +13,7 @@ public final class CoopCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (args.size() < 2) {
-            CommandHandler.sendMessage(sender, "Usage: coop <playerId> <target playerId>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Coop_usage);
             return;
         }
         
@@ -22,7 +23,7 @@ public final class CoopCommand implements CommandHandler {
             Player host = sender.getServer().getPlayerByUid(hostId);
             Player want = sender.getServer().getPlayerByUid(tid);
             if (host == null || want == null) {
-                CommandHandler.sendMessage(sender, "Player is offline.");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_is_offline);
                 return;
             }
             if (want.isInMultiplayer()) {
@@ -31,7 +32,7 @@ public final class CoopCommand implements CommandHandler {
             sender.getServer().getMultiplayerManager().applyEnterMp(want, hostId);
             sender.getServer().getMultiplayerManager().applyEnterMpReply(host, tid, true);
         } catch (Exception e) {
-            CommandHandler.sendMessage(sender, "Player id is not valid.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
         }
     }
 }

src/main/java/emu/grasscutter/command/commands/DropCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
 import emu.grasscutter.data.GameData;
@@ -17,12 +18,12 @@ public final class DropCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return;
         }
 
         if (args.size() < 1) {
-            CommandHandler.sendMessage(sender, "Usage: drop <itemId|itemName> [amount]");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Drop_usage);
             return;
         }
 
@@ -33,7 +34,7 @@ public final class DropCommand implements CommandHandler {
 
             ItemData itemData = GameData.getItemDataMap().get(item);
             if (itemData == null) {
-                CommandHandler.sendMessage(sender, "Invalid item id.");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_id);
                 return;
             }
 
@@ -48,9 +49,9 @@ public final class DropCommand implements CommandHandler {
                 EntityItem entity = new EntityItem(sender.getScene(), sender, itemData, sender.getPos().clone().addY(3f), amount);
                 sender.getScene().addEntity(entity);
             }
-            CommandHandler.sendMessage(sender, String.format("Dropped %s of %s.", amount, item));
+            CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().Drop_dropped_of, amount, item));
         } catch (NumberFormatException ignored) {
-            CommandHandler.sendMessage(sender, "Invalid item or player ID.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_or_player_id);
         }
     }
 }
\ No newline at end of file

src/main/java/emu/grasscutter/command/commands/EnterDungeonCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
 import emu.grasscutter.game.player.Player;
@@ -12,12 +13,12 @@ public final class EnterDungeonCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return;
         }
 
         if (args.size() < 1) {
-            CommandHandler.sendMessage(sender, "Usage: enterdungeon <dungeon id>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().EnterDungeon_usage);
             return;
         }
 
@@ -25,18 +26,18 @@ public final class EnterDungeonCommand implements CommandHandler {
             int dungeonId = Integer.parseInt(args.get(0));
             
             if (dungeonId == sender.getSceneId()) {
-            	CommandHandler.sendMessage(sender, "You are already in that dungeon");
+            	CommandHandler.sendMessage(sender, Grasscutter.getLanguage().EnterDungeon_you_in_that_dungeon);
             	return;
             }
             
             boolean result = sender.getServer().getDungeonManager().enterDungeon(sender.getSession().getPlayer(), 0, dungeonId);
-            CommandHandler.sendMessage(sender, "Changed to dungeon " + dungeonId);
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().EnterDungeon_changed_to_dungeon + dungeonId);
 
             if (!result) {
-                CommandHandler.sendMessage(sender, "Dungeon does not exist");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().EnterDungeon_dungeon_not_found);
             }
         } catch (Exception e) {
-            CommandHandler.sendMessage(sender, "Usage: enterdungeon <dungeon id>");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().EnterDungeon_usage);
         }
     }
 }

src/main/java/emu/grasscutter/command/commands/GiveAllCommand.java

@@ -24,7 +24,7 @@ public final class GiveAllCommand implements CommandHandler {
         switch (args.size()) {
             case 0: // *no args*
                 if (sender == null) {
-                    CommandHandler.sendMessage(null, "This usage can only be run in-game");
+                    CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
                     return;
                 }
                 target = sender.getUid();
@@ -34,11 +34,11 @@ public final class GiveAllCommand implements CommandHandler {
                 try {
                     target = Integer.parseInt(args.get(0));
                     if (Grasscutter.getGameServer().getPlayerByUid(target) == null) {
-                        CommandHandler.sendMessage(sender, "Invalid player ID.");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
                         return;
                     }
                 }catch (NumberFormatException ignored){
-                    CommandHandler.sendMessage(sender, "Invalid player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
                     return;
                 }
                 break;
@@ -53,28 +53,28 @@ public final class GiveAllCommand implements CommandHandler {
                         amount = Integer.parseInt(args.get(1));
                     }
                 } catch (NumberFormatException ignored) {
-                    CommandHandler.sendMessage(sender, "Invalid amount or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveAll_invalid_amount_or_playerId);
                     return;
                 }
                 break;
 
             default: // invalid
-                CommandHandler.sendMessage(null, "Usage: giveall [player] [amount]");
+                CommandHandler.sendMessage(null, Grasscutter.getLanguage().GiveAll_usage);
                 return;
         }
 
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
 
         this.giveAllItems(targetPlayer, amount);
-        CommandHandler.sendMessage(sender, "Giving all items done");
+        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveAll_done);
     }
 
     public void giveAllItems(Player player, int amount) {
-        CommandHandler.sendMessage(player, "Giving all items...");
+        CommandHandler.sendMessage(player, Grasscutter.getLanguage().GiveAll_item);
 
         for (AvatarData avatarData: GameData.getAvatarDataMap().values()) {
             //Exclude test avatar

src/main/java/emu/grasscutter/command/commands/GiveArtifactCommand.java

@@ -20,7 +20,7 @@ public final class GiveArtifactCommand implements CommandHandler {
 	public void execute(Player sender, List<String> args) {
 		int size = args.size(), target, itemId, mainPropId, level = 1;
 		ArrayList<Integer> appendPropIdList = new ArrayList<>();
-		String msg = "Usage: giveart|gart [player] <artifactId> <mainPropId> [<appendPropId>[,<times>]]... [level]";
+		String msg = Grasscutter.getLanguage().GiveArtifact_usage;
 
 		if (sender == null && size < 2) {
 			CommandHandler.sendMessage(null, msg);
@@ -70,14 +70,14 @@ public final class GiveArtifactCommand implements CommandHandler {
 
 		Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
 		if (targetPlayer == null) {
-			CommandHandler.sendMessage(sender, "Player not found.");
+			CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
 			return;
 		}
 
 		ItemData itemData = GameData.getItemDataMap().get(itemId);
 
 		if (itemData.getItemType() != ItemType.ITEM_RELIQUARY) {
-			CommandHandler.sendMessage(sender, "Invalid artifact ID.");
+			CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveArtifact_invalid_artifact_id);
 			return;
 		}
 
@@ -88,7 +88,7 @@ public final class GiveArtifactCommand implements CommandHandler {
 		item.getAppendPropIdList().addAll(appendPropIdList);
 		targetPlayer.getInventory().addItem(item, ActionReason.SubfieldDrop);
 
-		CommandHandler.sendMessage(sender, String.format("Given %s to %s.", itemId, target));
+		CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().GiveArtifact_given, itemId, target));
 	}
 }
 

src/main/java/emu/grasscutter/command/commands/GiveCharCommand.java

@@ -19,13 +19,13 @@ public final class GiveCharCommand implements CommandHandler {
         int target, avatarId, level = 1, ascension;
 
         if (sender == null && args.size() < 2) {
-            CommandHandler.sendMessage(null, "Usage: givechar <player> <itemId|itemName> [amount]");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().GiveChar_usage);
             return;
         }
 
         switch (args.size()) {
             default:
-                CommandHandler.sendMessage(sender, "Usage: givechar <player> <avatarId> [level]");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveChar_usage);
                 return;
             case 2:
                 try {
@@ -39,7 +39,7 @@ public final class GiveCharCommand implements CommandHandler {
                     }
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from avatar name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid avatar or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveChar_invalid_avatar_or_player_id);
                     return;
                 }
                 break;
@@ -47,7 +47,7 @@ public final class GiveCharCommand implements CommandHandler {
                 try {
                     target = Integer.parseInt(args.get(0));
                     if (Grasscutter.getGameServer().getPlayerByUid(target) == null) {
-                        CommandHandler.sendMessage(sender, "Invalid player ID.");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
                         return;
                     }
 
@@ -55,7 +55,7 @@ public final class GiveCharCommand implements CommandHandler {
                     level = Integer.parseInt(args.get(2));
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from avatar name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid avatar or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveChar_invalid_avatar_or_player_id);
                     return;
                 }
                 break;
@@ -63,19 +63,19 @@ public final class GiveCharCommand implements CommandHandler {
 
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
 
         AvatarData avatarData = GameData.getAvatarDataMap().get(avatarId);
         if (avatarData == null) {
-            CommandHandler.sendMessage(sender, "Invalid avatar id.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveChar_invalid_avatar_id);
             return;
         }
 
         // Check level.
         if (level > 90) {
-            CommandHandler.sendMessage(sender, "Invalid avatar level.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().GiveChar_invalid_avatar_level);
             return;
         }
 
@@ -94,6 +94,6 @@ public final class GiveCharCommand implements CommandHandler {
         avatar.recalcStats();
 
         targetPlayer.addAvatar(avatar);
-        CommandHandler.sendMessage(sender, String.format("Given %s with level %s to %s.", avatarId, level, target));
+        CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().GiveChar_given, avatarId, level, target));
     }
 }

src/main/java/emu/grasscutter/command/commands/GiveCommand.java

@@ -21,13 +21,13 @@ public final class GiveCommand implements CommandHandler {
     public void execute(Player sender, List<String> args) {
         int target, item, lvl, amount = 1, refinement = 0;
         if (sender == null && args.size() < 2) {
-            CommandHandler.sendMessage(null, "Usage: give <player> <itemId|itemName> [amount] [level]");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Give_usage);
             return;
         }
 
         switch (args.size()) {
             default: // *No args*
-                CommandHandler.sendMessage(sender, "Usage: give [player] <itemId|itemName> [amount]");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Give_usage);
                 return;
             case 1: // <itemId|itemName>
                 try {
@@ -36,7 +36,7 @@ public final class GiveCommand implements CommandHandler {
                     lvl = 1;
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from item name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid item id.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_id);
                     return;
                 }
                 break;
@@ -54,7 +54,7 @@ public final class GiveCommand implements CommandHandler {
                     }
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from item name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid item or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_or_player_id);
                     return;
                 }
                 break;
@@ -75,7 +75,7 @@ public final class GiveCommand implements CommandHandler {
 
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from item name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid item or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_or_player_id);
                     return;
                 }
                 break;
@@ -96,7 +96,7 @@ public final class GiveCommand implements CommandHandler {
                     }
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from item name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid item or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_or_player_id);
                     return;
                 }
                 break;
@@ -105,7 +105,7 @@ public final class GiveCommand implements CommandHandler {
                     target = Integer.parseInt(args.get(0));
 
                     if (Grasscutter.getGameServer().getPlayerByUid(target) == null) {
-                        CommandHandler.sendMessage(sender, "Invalid player ID.");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
                         return;
                     } else {
                         item = Integer.parseInt(args.get(1));
@@ -115,7 +115,7 @@ public final class GiveCommand implements CommandHandler {
                     }
                 } catch (NumberFormatException ignored) {
                     // TODO: Parse from item name using GM Handbook.
-                    CommandHandler.sendMessage(sender, "Invalid item or player ID.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_or_player_id);
                     return;
                 }
                 break;
@@ -124,23 +124,23 @@ public final class GiveCommand implements CommandHandler {
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
 
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
 
         ItemData itemData = GameData.getItemDataMap().get(item);
         if (itemData == null) {
-            CommandHandler.sendMessage(sender, "Invalid item id.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_item_id);
             return;
         }
         if (refinement != 0) {
             if (itemData.getItemType() == ItemType.ITEM_WEAPON) {
                 if (refinement < 1 || refinement > 5) {
-                    CommandHandler.sendMessage(sender, "Refinement must be between 1 and 5.");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Give_refinement_must_between_1_and_5);
                     return;
                 }
             } else {
-                CommandHandler.sendMessage(sender, "Refinement is only applicable to weapons.");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Give_refinement_only_applicable_weapons);
                 return;
             }
         }
@@ -148,13 +148,13 @@ public final class GiveCommand implements CommandHandler {
         this.item(targetPlayer, itemData, amount, lvl, refinement);
 
         if (!itemData.isEquip()) {
-            CommandHandler.sendMessage(sender, String.format("Given %s of %s to %s.", amount, item, target));
+            CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().Give_given, amount, item, target));
         } else if (itemData.getItemType() == ItemType.ITEM_WEAPON) {
             CommandHandler.sendMessage(sender,
-                    String.format("Given %s with level %s, refinement %s %s times to %s", item, lvl, refinement, amount, target));
+                    String.format(Grasscutter.getLanguage().Give_given_with_level_and_refinement, item, lvl, refinement, amount, target));
         } else {
             CommandHandler.sendMessage(sender,
-                    String.format("Given %s with level %s %s times to %s", item, lvl, amount, target));
+                    String.format(Grasscutter.getLanguage().Give_given_level, item, lvl, amount, target));
         }
     }
 

src/main/java/emu/grasscutter/command/commands/GodModeCommand.java

@@ -14,7 +14,7 @@ public final class GodModeCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return; // TODO: toggle player's godmode statue from console or other players
         }
 
@@ -26,7 +26,7 @@ public final class GodModeCommand implements CommandHandler {
                     target = sender.getUid();
                 }
             } catch (NumberFormatException e) {
-                CommandHandler.sendMessage(sender, "Invalid player id.");
+                CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_playerId);
                 return;
             }
         } else {
@@ -34,12 +34,14 @@ public final class GodModeCommand implements CommandHandler {
         }
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
 
         targetPlayer.setGodmode(!targetPlayer.inGodmode());
-        sender.dropMessage("Godmode is now " + (targetPlayer.inGodmode() ? "enabled" : "disabled") +
-                "for " + targetPlayer.getNickname() + " .");
+        sender.dropMessage(String.format(Grasscutter.getLanguage().Godmode_status,
+                (targetPlayer.inGodmode() ? Grasscutter.getLanguage().Enabled : Grasscutter.getLanguage().Disabled),
+                targetPlayer.getNickname()
+        ));
     }
 }

src/main/java/emu/grasscutter/command/commands/HealCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
 import emu.grasscutter.game.player.Player;
@@ -15,7 +16,7 @@ public final class HealCommand implements CommandHandler {
     @Override
     public void execute(Player sender, List<String> args) {
         if (sender == null) {
-            CommandHandler.sendMessage(null, "Run this command in-game.");
+            CommandHandler.sendMessage(null, Grasscutter.getLanguage().Run_this_command_in_game);
             return;
         }
         
@@ -30,6 +31,6 @@ public final class HealCommand implements CommandHandler {
                 entity.getWorld().broadcastPacket(new PacketAvatarLifeStateChangeNotify(entity.getAvatar()));
             }
         });
-        CommandHandler.sendMessage(sender, "All characters have been healed.");
+        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Heal_message);
     }
 }

src/main/java/emu/grasscutter/command/commands/HelpCommand.java

 package emu.grasscutter.command.commands;
 
+import emu.grasscutter.Grasscutter;
 import emu.grasscutter.command.Command;
 import emu.grasscutter.command.CommandHandler;
 import emu.grasscutter.command.CommandMap;
@@ -30,16 +31,16 @@ public final class HelpCommand implements CommandHandler {
         } else {
             String command = args.get(0);
             CommandHandler handler = CommandMap.getInstance().getHandler(command);
-            StringBuilder builder = new StringBuilder(player == null ? "\nHelp - " : "Help - ").append(command).append(": \n");
+            StringBuilder builder = new StringBuilder(player == null ? "\n" + Grasscutter.getLanguage().Help + " - " : Grasscutter.getLanguage().Help + " - ").append(command).append(": \n");
             if (handler == null) {
-                builder.append("No command found.");
+                builder.append(Grasscutter.getLanguage().No_command_found);
             } else {
                 Command annotation = handler.getClass().getAnnotation(Command.class);
 
                 builder.append("   ").append(annotation.description()).append("\n");
-                builder.append("   Usage: ").append(annotation.usage());
+                builder.append(Grasscutter.getLanguage().Help_usage).append(annotation.usage());
                 if (annotation.aliases().length >= 1) {
-                    builder.append("\n").append("   Aliases: ");
+                    builder.append("\n").append(Grasscutter.getLanguage().Help_aliases);
                     for (String alias : annotation.aliases()) {
                         builder.append(alias).append(" ");
                     }
@@ -55,13 +56,13 @@ public final class HelpCommand implements CommandHandler {
 
     void SendAllHelpMessage(Player player, List<Command> annotations) {
         if (player == null) {
-            StringBuilder builder = new StringBuilder("\nAvailable commands:\n");
+            StringBuilder builder = new StringBuilder("\n" + Grasscutter.getLanguage().Help_available_command + "\n");
             annotations.forEach(annotation -> {
                 builder.append(annotation.label()).append("\n");
                 builder.append("   ").append(annotation.description()).append("\n");
-                builder.append("   Usage: ").append(annotation.usage());
+                builder.append(Grasscutter.getLanguage().Help_usage).append(annotation.usage());
                 if (annotation.aliases().length >= 1) {
-                    builder.append("\n").append("   Aliases: ");
+                    builder.append("\n").append(Grasscutter.getLanguage().Help_aliases);
                     for (String alias : annotation.aliases()) {
                         builder.append(alias).append(" ");
                     }
@@ -72,13 +73,13 @@ public final class HelpCommand implements CommandHandler {
 
             CommandHandler.sendMessage(null, builder.toString());
         } else {
-            CommandHandler.sendMessage(player, "Available commands:");
+            CommandHandler.sendMessage(player, Grasscutter.getLanguage().Help_available_command);
             annotations.forEach(annotation -> {
                 StringBuilder builder = new StringBuilder(annotation.label()).append("\n");
                 builder.append("   ").append(annotation.description()).append("\n");
-                builder.append("   Usage: ").append(annotation.usage());
+                builder.append(Grasscutter.getLanguage().Help_usage).append(annotation.usage());
                 if (annotation.aliases().length >= 1) {
-                    builder.append("\n").append("   Aliases: ");
+                    builder.append("\n").append(Grasscutter.getLanguage().Help_aliases);
                     for (String alias : annotation.aliases()) {
                         builder.append(alias).append(" ");
                     }

src/main/java/emu/grasscutter/command/commands/KickCommand.java

@@ -17,14 +17,14 @@ public final class KickCommand implements CommandHandler {
 
         Player targetPlayer = Grasscutter.getGameServer().getPlayerByUid(target);
         if (targetPlayer == null) {
-            CommandHandler.sendMessage(sender, "Player not found.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found);
             return;
         }
 
         if (sender != null) {
-            CommandHandler.sendMessage(sender, String.format("Player [%s:%s] has kicked player [%s:%s]", sender.getAccount().getPlayerUid(), sender.getAccount().getUsername(), target, targetPlayer.getAccount().getUsername()));
+            CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().Kick_player_kick_player, sender.getAccount().getPlayerUid(), sender.getAccount().getUsername(), target, targetPlayer.getAccount().getUsername()));
         }
-        CommandHandler.sendMessage(sender, String.format("Kicking player [%s:%s]", target, targetPlayer.getAccount().getUsername()));
+        CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().Kick_server_player, target, targetPlayer.getAccount().getUsername()));
 
         targetPlayer.getSession().close();
     }

src/main/java/emu/grasscutter/command/commands/KillAllCommand.java

@@ -23,7 +23,7 @@ public final class KillAllCommand implements CommandHandler {
             switch (args.size()) {
                 case 0: // *No args*
                     if (sender == null) {
-                        CommandHandler.sendMessage(null, "Usage: killall [playerUid] [sceneId]");
+                        CommandHandler.sendMessage(null, Grasscutter.getLanguage().Kill_usage);
                         return;
                     }
                     mainScene = sender.getScene();
@@ -31,7 +31,7 @@ public final class KillAllCommand implements CommandHandler {
                 case 1: // [playerUid]
                     targetPlayer = Grasscutter.getGameServer().getPlayerByUid(Integer.parseInt(args.get(0)));
                     if (targetPlayer == null) {
-                        CommandHandler.sendMessage(sender, "Player not found or offline.");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found_or_offline);
                         return;
                     }
                     mainScene = targetPlayer.getScene();
@@ -39,18 +39,18 @@ public final class KillAllCommand implements CommandHandler {
                 case 2: // [playerUid] [sceneId]
                     targetPlayer = Grasscutter.getGameServer().getPlayerByUid(Integer.parseInt(args.get(0)));
                     if (targetPlayer == null) {
-                        CommandHandler.sendMessage(sender, "Player not found or offline.");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Player_not_found_or_offline);
                         return;
                     }
                     Scene scene = sender.getWorld().getSceneById(Integer.parseInt(args.get(1)));
                     if (scene == null) {
-                        CommandHandler.sendMessage(sender, "Scene not found in player world");
+                        CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Kill_scene_not_found_in_player_world);
                         return;
                     }
                     mainScene = scene;
                     break;
                 default:
-                    CommandHandler.sendMessage(sender, "Usage: killall [playerUid] [sceneId]");
+                    CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Kill_usage);
                     return;
             }
 
@@ -59,9 +59,9 @@ public final class KillAllCommand implements CommandHandler {
                     .filter(entity -> entity instanceof EntityMonster)
                     .toList();
             toKill.stream().forEach(entity -> mainScene.killEntity(entity, 0));
-            CommandHandler.sendMessage(sender, "Killing " + toKill.size() + " monsters in scene " + mainScene.getId());
+            CommandHandler.sendMessage(sender, String.format(Grasscutter.getLanguage().Kill_kill_monsters_in_scene, toKill.size(), mainScene.getId()));
         } catch (NumberFormatException ignored) {
-            CommandHandler.sendMessage(sender, "Invalid arguments.");
+            CommandHandler.sendMessage(sender, Grasscutter.getLanguage().Invalid_arguments);
         }
     }
 }