Fixes #134

src/main/java/vip/fubuki/playersync/sync/VanillaSync.java

@@ -24,6 +24,7 @@ import net.minecraft.world.level.storage.WorldData;
 import net.minecraftforge.event.OnDatapackSyncEvent;
 import net.minecraftforge.event.TickEvent;
 import net.minecraftforge.event.entity.player.PlayerEvent;
+import net.minecraftforge.event.entity.player.PlayerNegotiationEvent;
 import net.minecraftforge.event.server.ServerStoppedEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.ModList;
@@ -137,7 +138,52 @@ public class VanillaSync {
         }
     }
 
-    public static void doPlayerJoin(PlayerEvent.PlayerLoggedInEvent event) throws SQLException, CommandSyntaxException, IOException {
+    public static void doPlayerConnect(PlayerNegotiationEvent event) {
+        try {
+            String player_uuid = event.getProfile().getId().toString();
+            PlayerSync.LOGGER.info("Detected connection from player" + player_uuid + ",starting checking");
+            boolean online = false;
+            int lastServer = -1;
+
+            // First query: check basic player data and check whether player can join into server.
+            JDBCsetUp.QueryResult qr1 = JDBCsetUp.executeQuery("SELECT online, last_server FROM player_data WHERE uuid='" + player_uuid + "'");
+
+            try (ResultSet rs1 = qr1.resultSet()) {
+                if (!rs1.next()) {
+                    PlayerSync.LOGGER.info("A new-player connection detected");
+                    qr1.connection().close();
+                    return;
+                }
+                online = rs1.getBoolean("online");
+                lastServer = rs1.getInt("last_server");
+                qr1.connection().close();
+            }
+
+            // Second query: Check if player is already online on another server
+            if (online && lastServer != JdbcConfig.SERVER_ID.get()) {
+                JDBCsetUp.QueryResult qr2 = JDBCsetUp.executeQuery("SELECT last_update,enable FROM server_info WHERE id='" + lastServer + "'");
+                try (ResultSet rs2 = qr2.resultSet()) {
+                    if (rs2.next()) {
+                        long last_update = rs2.getLong("last_update");
+                        boolean enable = rs2.getBoolean("enable");
+                        if (enable && System.currentTimeMillis() < last_update + 300000.0) {
+                            event.getConnection().disconnect(Component.translatable("playersync.already_online"));
+                            qr2.connection().close();
+                            return;
+                        }
+                        JDBCsetUp.executeUpdate("UPDATE server_info SET enable= '0' WHERE id=" + lastServer);
+                    }
+                    qr2.connection().close();
+                }
+            }
+        } catch (Exception e) {
+            PlayerSync.LOGGER.error("SqlException detected!", e);
+            event.getConnection().disconnect(Component.translatable("playersync.sqlexception"));
+        }
+    }
+
+    public static void doPlayerJoin(PlayerEvent.PlayerLoggedInEvent event) {
+        try {
             String player_uuid = event.getEntity().getUUID().toString();
             PlayerSync.LOGGER.info("Starting synchronization for player " + player_uuid);
 
@@ -152,31 +198,16 @@ public class VanillaSync {
 
             if (!rs1.next()){
                 store(event.getEntity(), true);
+                JDBCsetUp.executeUpdate("UPDATE server_info SET last_update=" + System.currentTimeMillis() + " WHERE id=" + JdbcConfig.SERVER_ID.get());
+                JDBCsetUp.executeUpdate("UPDATE player_data SET online= '1',last_server=" + JdbcConfig.SERVER_ID.get() + " WHERE uuid='" + player_uuid + "'");
+                rs1.close();
                 return;
             }
-        boolean online = rs1.getBoolean("online");
-        int lastServer = rs1.getInt("last_server");
 
             // Second query: retrieve full player data
             JDBCsetUp.QueryResult qr2 = JDBCsetUp.executeQuery("SELECT * FROM player_data WHERE uuid='" + player_uuid + "'");
             ResultSet rs2 = qr2.resultSet();
 
-        // Check if player is already online on another server
-        if (online && lastServer != JdbcConfig.SERVER_ID.get()) {
-            JDBCsetUp.QueryResult qr3 = JDBCsetUp.executeQuery("SELECT last_update,enable FROM server_info WHERE id='" + lastServer + "'");
-            ResultSet rs3 = qr3.resultSet();
-            if (rs3.next()){
-                long last_update = rs3.getLong("last_update");
-                boolean enable = rs3.getBoolean("enable");
-                if (enable && System.currentTimeMillis() < last_update + 300000.0){
-                    event.getEntity().removeTag("player_synced");
-                    serverPlayer.connection.disconnect(Component.translatable("playersync.already_online"));
-                    return;
-                }
-                JDBCsetUp.executeUpdate("UPDATE server_info SET enable= '0' WHERE id=" + lastServer);
-            }
-            rs3.close();
-        }
             JDBCsetUp.executeUpdate("UPDATE server_info SET last_update=" + System.currentTimeMillis() + " WHERE id=" + JdbcConfig.SERVER_ID.get());
             JDBCsetUp.executeUpdate("UPDATE player_data SET online= '1',last_server=" + JdbcConfig.SERVER_ID.get() + " WHERE uuid='" + player_uuid + "'");
 
@@ -237,6 +268,20 @@ public class VanillaSync {
             serverPlayer.addTag("player_synced");
 
             rs2.close();
+        } catch (Exception e) {
+            PlayerSync.LOGGER.error("Internal Exception detected!", e);
+        }
+    }
+
+    @SubscribeEvent
+    public static void onPlayerConnect(PlayerNegotiationEvent event) {
+        executorService.submit(() -> {
+            try {
+                doPlayerConnect(event);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        });
     }
 
     @SubscribeEvent

src/main/resources/assets/playersync/lang/en_us.json

@@ -1,5 +1,7 @@
 {
   "playersync.item_placeholder_description": "Item is unknown on this server. This can either\nbe a modded item, an added, or a removed vanilla\nitem.\nThis voucher will automatically be replaced with\nthe corresponding item when joining a server\nwhere the item is known.",
+  "playersync.placeholder_titel_override": "Item Voucher",
   "playersync.item_placeholder_title": "Item Voucher",
-  "playersync.already_online": "You can't join more than one synchronization server at the same time."
+  "playersync.already_online": "You can't join more than one synchronization server at the same time.",
+  "playersync.sqlexception": "SqlException detected!Connection lost,please contact with your admin."
 }

src/main/resources/assets/playersync/lang/zh_cn.json

@@ -1,5 +1,7 @@
 {
-  "playersync.item_placeholder_description": "物品在此服务器未知。这可能是一个模组物品,或是不同版本的原版物品。\n这张券将会在加入可识别此物品的服务器后自动替换为对应物品。",
-  "playersync.item_placeholder_title": "物品券",
-  "playersync.already_online": "你不能同时加入多个同步的服务器。"
+  "playersync.item_placeholder_description": "在这个服务器上,该物品是未知的\n它可能曾是一个其他已被移除的mod的物品,或者被移除的原版物品\n这一凭证将在加入拥有该物品的服务器时自动转换为对应物品",
+  "playersync.placeholder_titel_override": "未知物品凭证",
+  "playersync.item_placeholder_title": "未知物品凭证",
+  "playersync.already_online": "你不能同时加入多个在线的数据互通的服务器",
+  "playersync.sqlexception": "检测到Sql异常!连接已中断,请联系管理员"
 }