FightSystem_Main/src/de/steamwar/fightsystem/FightSystem.java

@@ -42,7 +42,8 @@ import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 import org.bukkit.plugin.java.JavaPlugin;
 
-import java.util.Date;
+import java.time.Instant;
+import java.time.temporal.ChronoField;
 import java.util.logging.Level;
 
 public class FightSystem extends JavaPlugin {
@@ -146,7 +147,7 @@ public class FightSystem extends JavaPlugin {
             Fight.getBlueTeam().setSchem(Schematic.getSchemFromDB(Config.PrepareSchemID));
         }
 
-        ISAPRIL = new Date().getDay() == 1 && new Date().getMonth() == 4;
+        ISAPRIL = Instant.now().get(ChronoField.DAY_OF_MONTH) == 1 && Instant.now().get(ChronoField.MONTH_OF_YEAR) == 4;
     }
 
     @Override

FightSystem_Main/src/de/steamwar/fightsystem/listener/DenyWorldInteraction.java

@@ -94,7 +94,7 @@ public class DenyWorldInteraction implements Listener {
         }
     }
 
-    @EventHandler()
+    @EventHandler
     public void onPlayerJoin(PlayerJoinEvent event) {
         if(FightSystem.ISAPRIL) {
             PacketContainer demo = ProtocolLibrary.getProtocolManager().createPacket(PacketType.Play.Server.GAME_STATE_CHANGE);