fix: limit the queue amount on the database executor

src/main/java/me/chayapak1/chomens_bot/commands/FindAltsCommand.java

@@ -33,6 +33,8 @@ public class FindAltsCommand extends Command {
 
         if (bot.database == null) throw new CommandException(Component.text("Database is not enabled in the bot's config"));
 
+        bot.database.checkOverloaded();
+
         final String flag = context.getString(false, true);
 
         final boolean allServer = flag.equals("-allserver");

src/main/java/me/chayapak1/chomens_bot/commands/MailCommand.java

@@ -40,6 +40,8 @@ public class MailCommand extends Command {
 
         if (bot.database == null) throw new CommandException(Component.text("Database is not enabled in the bot's config"));
 
+        bot.database.checkOverloaded();
+
         final PlayerEntry sender = context.sender;
 
         // kinda messy ngl

src/main/java/me/chayapak1/chomens_bot/commands/SeenCommand.java

@@ -38,6 +38,8 @@ public class SeenCommand extends Command {
 
         if (bot.database == null) throw new CommandException(Component.text("Database is not enabled in the bot's config"));
 
+        bot.database.checkOverloaded();
+
         final String player = context.getString(true, true);
 
         boolean online = false;

src/main/java/me/chayapak1/chomens_bot/plugins/DatabasePlugin.java

@@ -4,11 +4,14 @@ import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import me.chayapak1.chomens_bot.Bot;
 import me.chayapak1.chomens_bot.Configuration;
 import me.chayapak1.chomens_bot.Main;
+import me.chayapak1.chomens_bot.command.CommandException;
 import me.chayapak1.chomens_bot.util.LoggerUtilities;
+import net.kyori.adventure.text.Component;
 
 import java.sql.*;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadPoolExecutor;
 
 public class DatabasePlugin {
     public static final ExecutorService executorService = Executors.newFixedThreadPool(
@@ -33,6 +36,14 @@ public class DatabasePlugin {
         for (Bot bot : Main.bots) bot.database = this;
     }
 
+    public void checkOverloaded () throws CommandException {
+        final ThreadPoolExecutor threadPoolExecutor = (ThreadPoolExecutor) executorService;
+
+        if (threadPoolExecutor.getQueue().size() > 20) throw new CommandException(
+                Component.text("The executor service is filled with requests!")
+        );
+    }
+
     public boolean execute (String query) throws SQLException {
         final Statement statement = connection.createStatement();