Fix concurrency

Signed-off-by: Lixfel <agga-games@gmx.de>

src/de/steamwar/bungeecore/sql/UserElo.java

@@ -26,15 +26,16 @@ import net.md_5.bungee.api.connection.ProxiedPlayer;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class UserElo {
     private UserElo() {}
 
     public static final int ELO_DEFAULT = 1000;
 
-    private static final Map<String, Map<Integer, Optional<Integer>>> gameModeUserEloCache = new HashMap<>();
-    private static final Map<String, Integer> maxEloCache = new HashMap<>();
-    private static final Map<Integer, String> emblemCache = new HashMap<>();
+    private static final Map<String, Map<Integer, Optional<Integer>>> gameModeUserEloCache = new ConcurrentHashMap<>();
+    private static final Map<String, Integer> maxEloCache = new ConcurrentHashMap<>();
+    private static final Map<Integer, String> emblemCache = new ConcurrentHashMap<>();
 
     private static final Statement elo = new Statement("SELECT Elo FROM UserElo WHERE UserID = ? AND GameMode = ? AND Season = ?");
     private static final Statement setElo = new Statement("INSERT INTO UserElo (Season, GameMode, UserID, Elo) VALUES (?, ?, ?, ?) ON DUPLICATE KEY UPDATE Elo = VALUES(Elo)");