diff --git a/src/main/java/me/chayapak1/chomens_bot/command/Command.java b/src/main/java/me/chayapak1/chomens_bot/command/Command.java
index dc1013ac..bbf0999b 100644
--- a/src/main/java/me/chayapak1/chomens_bot/command/Command.java
+++ b/src/main/java/me/chayapak1/chomens_bot/command/Command.java
@@ -6,9 +6,9 @@ import java.util.Arrays;
 
 public abstract class Command {
     public final String name;
-    public String description;
+    public final String description;
     public String[] usages;
-    public String[] aliases;
+    public final String[] aliases;
     public final TrustLevel trustLevel;
     public final boolean consoleOnly;
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/commands/MailCommand.java b/src/main/java/me/chayapak1/chomens_bot/commands/MailCommand.java
index 1b591805..0dc0047a 100644
--- a/src/main/java/me/chayapak1/chomens_bot/commands/MailCommand.java
+++ b/src/main/java/me/chayapak1/chomens_bot/commands/MailCommand.java
@@ -116,7 +116,7 @@ public class MailCommand extends Command {
 
                     int senderMailSize = 0;
                     for (Mail mail : mails) {
-                        if (!mail.sentTo.equals(sender.profile.getName())) continue;
+                        if (!mail.sentTo().equals(sender.profile.getName())) continue;
                         senderMailSize++;
                     }
 
@@ -130,9 +130,9 @@ public class MailCommand extends Command {
 
                     int count = 1;
                     for (Mail mail : mails) {
-                        if (!mail.sentTo.equals(sender.profile.getName())) continue;
+                        if (!mail.sentTo().equals(sender.profile.getName())) continue;
 
-                        final Instant instant = Instant.ofEpochMilli(mail.timeSent);
+                        final Instant instant = Instant.ofEpochMilli(mail.timeSent());
                         final ZoneId zoneId = ZoneId.systemDefault();
                         final OffsetDateTime localDateTime = OffsetDateTime.ofInstant(instant, zoneId);
 
@@ -148,7 +148,7 @@ public class MailCommand extends Command {
                                         Component.text(count).color(ColorUtilities.getColorByString(bot.config.colorPalette.number)),
                                         Component.text("-").color(NamedTextColor.DARK_GRAY),
 
-                                        Component.text(mail.sentBy).color(ColorUtilities.getColorByString(bot.config.colorPalette.username)),
+                                        Component.text(mail.sentBy()).color(ColorUtilities.getColorByString(bot.config.colorPalette.username)),
                                         Component
                                                 .text("[Hover here for more info]")
                                                 .color(NamedTextColor.GREEN)
@@ -159,11 +159,11 @@ public class MailCommand extends Command {
                                                                                 Time sent: %s
                                                                                 Server: %s""",
                                                                         Component.text(formattedTime).color(ColorUtilities.getColorByString(bot.config.colorPalette.string)),
-                                                                        Component.text(mail.server).color(ColorUtilities.getColorByString(bot.config.colorPalette.string))
+                                                                        Component.text(mail.server()).color(ColorUtilities.getColorByString(bot.config.colorPalette.string))
                                                                 ).color(NamedTextColor.GREEN)
                                                         )
                                                 ),
-                                        Component.text(mail.contents).color(NamedTextColor.WHITE)
+                                        Component.text(mail.contents()).color(NamedTextColor.WHITE)
                                 ).color(NamedTextColor.GREEN)
                         );
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/commands/ScreenshareCommand.java b/src/main/java/me/chayapak1/chomens_bot/commands/ScreenshareCommand.java
index 3a6422ec..fa2f18d6 100644
--- a/src/main/java/me/chayapak1/chomens_bot/commands/ScreenshareCommand.java
+++ b/src/main/java/me/chayapak1/chomens_bot/commands/ScreenshareCommand.java
@@ -84,9 +84,7 @@ public class ScreenshareCommand extends Command {
                             .append(Component.text(fps).color(ColorUtilities.getColorByString(bot.config.colorPalette.number)))
                             .color(ColorUtilities.getColorByString(bot.config.colorPalette.defaultColor));
                 }
-                default -> {
-                    throw new CommandException(Component.text("Invalid action"));
-                }
+                default -> throw new CommandException(Component.text("Invalid action"));
             }
         } catch (NumberFormatException e) {
             throw new CommandException(Component.text("Invalid integer"));
diff --git a/src/main/java/me/chayapak1/chomens_bot/commands/TPSBarCommand.java b/src/main/java/me/chayapak1/chomens_bot/commands/TPSBarCommand.java
index bc0366a2..cad9b62b 100644
--- a/src/main/java/me/chayapak1/chomens_bot/commands/TPSBarCommand.java
+++ b/src/main/java/me/chayapak1/chomens_bot/commands/TPSBarCommand.java
@@ -44,9 +44,7 @@ public class TPSBarCommand extends Command {
                         .append(Component.text("disabled").color(NamedTextColor.RED))
                         .color(ColorUtilities.getColorByString(bot.config.colorPalette.defaultColor));
             }
-            default -> {
-                throw new CommandException(Component.text("Invalid action"));
-            }
+            default -> throw new CommandException(Component.text("Invalid action"));
         }
     }
 }
diff --git a/src/main/java/me/chayapak1/chomens_bot/commands/ValidateCommand.java b/src/main/java/me/chayapak1/chomens_bot/commands/ValidateCommand.java
index 7d700b82..a64bd89f 100644
--- a/src/main/java/me/chayapak1/chomens_bot/commands/ValidateCommand.java
+++ b/src/main/java/me/chayapak1/chomens_bot/commands/ValidateCommand.java
@@ -2,7 +2,6 @@ package me.chayapak1.chomens_bot.commands;
 
 import me.chayapak1.chomens_bot.command.Command;
 import me.chayapak1.chomens_bot.command.CommandContext;
-import me.chayapak1.chomens_bot.command.CommandException;
 import me.chayapak1.chomens_bot.command.TrustLevel;
 import me.chayapak1.chomens_bot.command.contexts.ConsoleCommandContext;
 import me.chayapak1.chomens_bot.command.contexts.DiscordCommandContext;
@@ -22,7 +21,7 @@ public class ValidateCommand extends Command {
     }
 
     @Override
-    public Component execute (CommandContext context) throws CommandException {
+    public Component execute (CommandContext context) {
         // <red>Trusted - 1
         // <dark_red>Admin - 2
         // .......
diff --git a/src/main/java/me/chayapak1/chomens_bot/data/eval/EvalFunction.java b/src/main/java/me/chayapak1/chomens_bot/data/eval/EvalFunction.java
index 94cd7a15..5fa60c36 100644
--- a/src/main/java/me/chayapak1/chomens_bot/data/eval/EvalFunction.java
+++ b/src/main/java/me/chayapak1/chomens_bot/data/eval/EvalFunction.java
@@ -17,13 +17,6 @@ public class EvalFunction {
 
     public Output execute (Object... args) throws Exception { return null; }
 
-    public static class Output {
-        public final String message;
-        public final boolean parseJSON;
-
-        public Output (String message, boolean parseJSON) {
-            this.message = message;
-            this.parseJSON = parseJSON;
-        }
+    public record Output(String message, boolean parseJSON) {
     }
 }
diff --git a/src/main/java/me/chayapak1/chomens_bot/data/mail/Mail.java b/src/main/java/me/chayapak1/chomens_bot/data/mail/Mail.java
index 4adb4f0d..19a317b6 100644
--- a/src/main/java/me/chayapak1/chomens_bot/data/mail/Mail.java
+++ b/src/main/java/me/chayapak1/chomens_bot/data/mail/Mail.java
@@ -3,13 +3,7 @@ package me.chayapak1.chomens_bot.data.mail;
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
-public class Mail {
-    public final String sentBy;
-    public final String sentTo;
-    public final long timeSent;
-    public final String server;
-    public final String contents;
-
+public record Mail(String sentBy, String sentTo, long timeSent, String server, String contents) {
     @JsonCreator
     public Mail (
             @JsonProperty("sentBy") String sentBy,
diff --git a/src/main/java/me/chayapak1/chomens_bot/data/player/PlayerEntry.java b/src/main/java/me/chayapak1/chomens_bot/data/player/PlayerEntry.java
index 1e75cf05..7de2380f 100644
--- a/src/main/java/me/chayapak1/chomens_bot/data/player/PlayerEntry.java
+++ b/src/main/java/me/chayapak1/chomens_bot/data/player/PlayerEntry.java
@@ -14,7 +14,7 @@ public class PlayerEntry {
     public GameMode gamemode;
     public int latency;
     public Component displayName;
-    public List<String> usernames = new ArrayList<>();
+    public final List<String> usernames = new ArrayList<>();
     public final long expiresAt;
     public PublicKey publicKey;
     public final byte[] keySignature;
diff --git a/src/main/java/me/chayapak1/chomens_bot/data/team/Team.java b/src/main/java/me/chayapak1/chomens_bot/data/team/Team.java
index 39b95ccc..04f975a0 100644
--- a/src/main/java/me/chayapak1/chomens_bot/data/team/Team.java
+++ b/src/main/java/me/chayapak1/chomens_bot/data/team/Team.java
@@ -12,7 +12,7 @@ import java.util.List;
 
 public class Team {
     public String teamName;
-    public List<String> players;
+    public final List<String> players;
     public Component displayName;
     public boolean friendlyFire;
     public boolean seeFriendlyInvisibles;
diff --git a/src/main/java/me/chayapak1/chomens_bot/plugins/DiscordPlugin.java b/src/main/java/me/chayapak1/chomens_bot/plugins/DiscordPlugin.java
index 6a9a9899..def5d0d5 100644
--- a/src/main/java/me/chayapak1/chomens_bot/plugins/DiscordPlugin.java
+++ b/src/main/java/me/chayapak1/chomens_bot/plugins/DiscordPlugin.java
@@ -43,7 +43,7 @@ public class DiscordPlugin extends ListenerAdapter {
 
     public final String prefix;
 
-    public Component messagePrefix;
+    public final Component messagePrefix;
 
     public final String discordUrl;
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/plugins/EvalPlugin.java b/src/main/java/me/chayapak1/chomens_bot/plugins/EvalPlugin.java
index b42453c2..4ef42158 100644
--- a/src/main/java/me/chayapak1/chomens_bot/plugins/EvalPlugin.java
+++ b/src/main/java/me/chayapak1/chomens_bot/plugins/EvalPlugin.java
@@ -66,7 +66,7 @@ public class EvalPlugin {
 
                     if (output == null) return;
 
-                    socket.emit("functionOutput:" + function.name, output.message, output.parseJSON);
+                    socket.emit("functionOutput:" + function.name, output.message(), output.parseJSON());
                 } catch (Exception ignored) { }
             }).start());
         }
diff --git a/src/main/java/me/chayapak1/chomens_bot/plugins/MailPlugin.java b/src/main/java/me/chayapak1/chomens_bot/plugins/MailPlugin.java
index cfe7b4b4..da61a672 100644
--- a/src/main/java/me/chayapak1/chomens_bot/plugins/MailPlugin.java
+++ b/src/main/java/me/chayapak1/chomens_bot/plugins/MailPlugin.java
@@ -53,7 +53,7 @@ public class MailPlugin implements PlayersPlugin.Listener {
             final List<Mail> mails = list();
 
             for (Mail mail : mails) {
-                if (!mail.sentTo.equals(name)) continue;
+                if (!mail.sentTo().equals(name)) continue;
 
                 sendToTargetSize++;
             }
@@ -77,11 +77,11 @@ public class MailPlugin implements PlayersPlugin.Listener {
         try {
             final PreparedStatement statement = bot.database.connection.prepareStatement(INSERT_MAIL);
 
-            statement.setString(1, mail.sentBy);
-            statement.setString(2, mail.sentTo);
-            statement.setLong(3, mail.timeSent);
-            statement.setString(4, mail.server);
-            statement.setString(5, mail.contents);
+            statement.setString(1, mail.sentBy());
+            statement.setString(2, mail.sentTo());
+            statement.setLong(3, mail.timeSent());
+            statement.setString(4, mail.server());
+            statement.setString(5, mail.contents());
 
             statement.executeUpdate();
         } catch (SQLException e) {
diff --git a/src/main/java/me/chayapak1/chomens_bot/plugins/ScreensharePlugin.java b/src/main/java/me/chayapak1/chomens_bot/plugins/ScreensharePlugin.java
index e1867357..2bf9b2f8 100644
--- a/src/main/java/me/chayapak1/chomens_bot/plugins/ScreensharePlugin.java
+++ b/src/main/java/me/chayapak1/chomens_bot/plugins/ScreensharePlugin.java
@@ -108,11 +108,11 @@ public class ScreensharePlugin {
         private final Bot bot;
 
         public String[][] screen;
-        public int width;
-        public int height;
-        public Vector3i pos;
+        public final int width;
+        public final int height;
+        public final Vector3i pos;
 
-        public ArrayList<String> tags = new ArrayList<>();
+        public final ArrayList<String> tags = new ArrayList<>();
 
         public Screen (Bot bot, int width, int height, Vector3i pos) {
             screen = new String[width][height];
diff --git a/src/main/java/me/chayapak1/chomens_bot/song/NBSConverter.java b/src/main/java/me/chayapak1/chomens_bot/song/NBSConverter.java
index 2ff9b48a..9a665b79 100644
--- a/src/main/java/me/chayapak1/chomens_bot/song/NBSConverter.java
+++ b/src/main/java/me/chayapak1/chomens_bot/song/NBSConverter.java
@@ -317,6 +317,7 @@ public class NBSConverter implements Converter {
         List<String> list = new ArrayList<>();
 
         InputStream is = ClassLoader.getSystemClassLoader().getResourceAsStream(name);
+        assert is != null;
         BufferedReader reader = new BufferedReader(new InputStreamReader(is));
         JsonArray json = JsonParser.parseReader(reader).getAsJsonArray();
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/song/Song.java b/src/main/java/me/chayapak1/chomens_bot/song/Song.java
index f61bc2e5..c40483db 100644
--- a/src/main/java/me/chayapak1/chomens_bot/song/Song.java
+++ b/src/main/java/me/chayapak1/chomens_bot/song/Song.java
@@ -29,7 +29,7 @@ public class Song {
     public String songOriginalAuthor;
     public String songDescription;
 
-    public String tracks;
+    public final String tracks;
 
     public final boolean nbs;
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/util/ComponentUtilities.java b/src/main/java/me/chayapak1/chomens_bot/util/ComponentUtilities.java
index c9ace3e9..cc16ccd6 100644
--- a/src/main/java/me/chayapak1/chomens_bot/util/ComponentUtilities.java
+++ b/src/main/java/me/chayapak1/chomens_bot/util/ComponentUtilities.java
@@ -73,6 +73,7 @@ public class ComponentUtilities {
         Map<String, String> map = new HashMap<>();
 
         InputStream is = ClassLoader.getSystemClassLoader().getResourceAsStream(name);
+        assert is != null;
         BufferedReader reader = new BufferedReader(new InputStreamReader(is));
         JsonObject json = JsonParser.parseReader(reader).getAsJsonObject();
 
diff --git a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusDecoder.java b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusDecoder.java
index 89b17675..ce3aefc5 100644
--- a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusDecoder.java
+++ b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusDecoder.java
@@ -5,10 +5,10 @@ import org.concentus.OpusException;
 
 public class JavaOpusDecoder {
     protected OpusDecoder opusDecoder;
-    protected short[] buffer;
-    protected int sampleRate;
-    protected int frameSize;
-    protected int maxPayloadSize;
+    protected final short[] buffer;
+    protected final int sampleRate;
+    protected final int frameSize;
+    protected final int maxPayloadSize;
 
     public JavaOpusDecoder (int sampleRate, int frameSize, int maxPayloadSize) {
         this.sampleRate = sampleRate;
diff --git a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder.java b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder.java
index 9b3dca31..0767e6d7 100644
--- a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder.java
+++ b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder.java
@@ -5,10 +5,10 @@ import org.concentus.OpusEncoder;
 
 public class JavaOpusEncoder {
     public OpusEncoder opusEncoder;
-    public byte[] buffer;
-    public int sampleRate;
-    public int frameSize;
-    public de.maxhenkel.opus4j.OpusEncoder.Application application;
+    public final byte[] buffer;
+    public final int sampleRate;
+    public final int frameSize;
+    public final de.maxhenkel.opus4j.OpusEncoder.Application application;
 
     public JavaOpusEncoder (int sampleRate, int frameSize, int maxPayloadSize, de.maxhenkel.opus4j.OpusEncoder.Application application) {
         this.sampleRate = sampleRate;
diff --git a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder2.java b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder2.java
index 2b94577d..391fa792 100644
--- a/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder2.java
+++ b/src/main/java/me/chayapak1/chomens_bot/voiceChat/mic/JavaOpusEncoder2.java
@@ -5,11 +5,11 @@ import org.concentus.OpusEncoder;
 
 public class JavaOpusEncoder2 {
     public OpusEncoder opusEncoder;
-    public byte[] buffer;
-    public int sampleRate;
-    public int frameSize;
-    public int maxPayloadSize;
-    public OpusApplication application;
+    public final byte[] buffer;
+    public final int sampleRate;
+    public final int frameSize;
+    public final int maxPayloadSize;
+    public final OpusApplication application;
 
     public JavaOpusEncoder2 (int sampleRate, int frameSize, int maxPayloadSize, OpusApplication application) {
         this.sampleRate = sampleRate;