Cần giúp đỡ về kết nối mysql trong java

em có class sau về BXH, dữ liệu e lấy ở cột user, e có 2 bảng xh là top level và top coin… nhưng khi chạy thì nó ko có dữ liệu người chơi in ra… ai có thể tìm ra nguyên nhân ko ạ @@

/*

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  */
  package main.server;

import java.util.ArrayList;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Timer;
import java.util.Date;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimerTask;

/**
*

• @author ASD
  */
  public class BangXHManager {

  public static class BangXHEntry {
  int index;
  int iddb;
  int nXH;
  }

  public static final String[] bangXHString = new String[]{“Top Level”, “Top Coin”};
  public static final String[] bangXHString1 = new String[]{“Level”, “Coin”};
  @SuppressWarnings(“unchecked”)
  public static final ArrayList bangXH[] = new ArrayList[2];
  public static final Timer t = new Timer(true);

  public static void init() {
  for(int i = 0; i < bangXH.length; i++)
  bangXH[i] = new ArrayList<>();
  Calendar cl = GregorianCalendar.getInstance();
  Date d = new Date();
  cl.setTime(d);
  cl.set(Calendar.HOUR_OF_DAY, 0);
  cl.set(Calendar.MINUTE, 0);
  cl.set(Calendar.SECOND, 0);
  cl.add(Calendar.DATE, 1);
  t.schedule(new TimerTask() {
  @Override
  public void run() {
  System.out.println(“Refresh BXH”);
  for(int i = 0; i < bangXHString.length; i++)
  refreshXH(i);
  }
  }, cl.getTime(), 86400000L);
  }

  public static void refreshXH(int type) {
  bangXH[type].clear();
  ArrayList bxh = bangXH[type];
  switch(type) {
  case 0:
  try {
  int i = 0;
  ResultSet red = SQLManager.stat.executeQuery(“SELECT id,lv FROM user ORDER BY lv DESC LIMIT 1, 100;”);
  while(red.next()) {
  int iddb = red.getInt(“id”);
  int lv = red.getInt(“lv”);
  if(iddb < 3)
  continue;
  if(i < 100) {
  BangXHEntry bXHE = new BangXHEntry();
  bXHE.iddb = iddb;
  bXHE.index = i;
  bXHE.nXH = lv;
  bxh.add(bXHE);
  }
  SQLManager.stat.executeUpdate(“UPDATE user SET top=’”+i+"’ WHERE id="+iddb+" LIMIT 1;");
  i++;
  }
  } catch(SQLException e) {
  e.printStackTrace();
  }
  break;

       case 1:
           try {
               int i = 0;
               ResultSet red = SQLManager.stat.executeQuery("SELECT `id`,`coin` FROM `user` ORDER BY `coin` DESC ;");
               while(red.next()) {
                   int iddb = red.getInt("id");
                   int coin = red.getInt("coin");
                   if(iddb < 3)
                       continue;
                   BangXHEntry bXHE = new BangXHEntry();
                   bXHE.iddb = iddb;
                   bXHE.index = i++;
                   bXHE.nXH = coin;
                   bxh.add(bXHE);
               }
           } catch(SQLException e) {
               e.printStackTrace();
           }
           break;
  
       
   }
  

  }

  public static final BangXHEntry[] getBangXH(int type, int page) {
  ArrayList bxh = bangXH[type];
  int index = page*10, lent = 0;
  if(index < bxh.size())
  lent = (bxh.size()-index)>10?10:(bxh.size()-index);
  BangXHEntry[] bxhA = new BangXHEntry[lent];
  for(int i = 0; i < lent; i++)
  bxhA[i] = bxh.get(index+i);
  return bxhA;
  }

}