fix: maybe some more concurrent fard fix

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

@@ -10,10 +10,13 @@ import me.chayapak1.chomens_bot.util.PersistentDataUtilities;
 import java.time.Instant;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.locks.ReentrantLock;
 
 public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
     public static ObjectNode playersObject = (ObjectNode) PersistentDataUtilities.getOrDefault("players", JsonNodeFactory.instance.objectNode());
 
+    public static final ReentrantLock lock = new ReentrantLock();
+
     private final Bot bot;
 
     public PlayersPersistentDataPlugin (Bot bot) {
@@ -24,6 +27,8 @@ public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
 
     @Override
     public synchronized void playerJoined(PlayerEntry target) {
+        lock.lock();
+
         final JsonNode originalElement = playersObject.get(target.profile.getName());
 
         ObjectNode object;
@@ -35,9 +40,12 @@ public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
         } else if (originalElement instanceof ObjectNode) {
             object = (ObjectNode) originalElement;
         } else {
+            lock.unlock();
             return;
         }
 
+        lock.unlock();
+
         bot.executorService.submit(() -> {
             final CompletableFuture<String> future = bot.players.getPlayerIP(target);
 
@@ -62,9 +70,13 @@ public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
 
     // is this bad?
     private synchronized void setPersistentEntry (PlayerEntry target, ObjectNode object) {
+        lock.lock();
+
         playersObject.set(getName(target), object);
 
         PersistentDataUtilities.put("players", playersObject);
+
+        lock.unlock();
     }
 
     private String getName(PlayerEntry target) {
@@ -73,6 +85,8 @@ public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
 
     @Override
     public synchronized void playerLeft(PlayerEntry target) {
+        lock.lock();
+
         if (!playersObject.has(getName(target))) return;
 
         final ObjectNode player = (ObjectNode) playersObject.get(getName(target));
@@ -84,5 +98,7 @@ public class PlayersPersistentDataPlugin extends PlayersPlugin.Listener {
         player.set("lastSeen", object);
 
         PersistentDataUtilities.put("players", playersObject);
+
+        lock.unlock();
     }
 }