InventoryClickevent error

How can i fix this

Code:

[13:42:34 ERROR]: Could not pass event InventoryClickEvent to UndroppableItem v0.3
java.lang.NullPointerException: null
        at en.dev.undroppableitem.listener.PlayerInteractEntityListener.onInventoryClick(PlayerInteractEntityListener.java:20) ~[?:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor4.execute(Unknown Source) ~[?:?]
        at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.16.5.jar:git-Paper-575]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.16.5.jar:git-Paper-575]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.16.5.jar:git-Paper-575]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:607) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.PlayerConnection.a(PlayerConnection.java:2687) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.PacketPlayInWindowClick.a(SourceFile:32) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.PacketPlayInWindowClick.a(SourceFile:10) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:35) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.TickTask.run(SourceFile:18) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.MinecraftServer.bb(MinecraftServer.java:1252) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.MinecraftServer.executeNext(MinecraftServer.java:1245) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.MinecraftServer.sleepForTick(MinecraftServer.java:1206) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:1120) ~[patched_1.16.5.jar:git-Paper-575]
        at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$a$0(MinecraftServer.java:289) ~[patched_1.16.5.jar:git-Paper-575]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_281]
>

Code:

import en.dev.undroppableitem.Main;
import org.bukkit.inventory.*;
import org.bukkit.enchantments.Enchantment;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.inventory.InventoryClickEvent;
import org.bukkit.event.inventory.InventoryDragEvent;
import org.bukkit.inventory.Inventory;

public class PlayerInteractEntityListener implements Listener {
  @EventHandler
  public void onInventoryClick(InventoryClickEvent event) {
      if (event.getClick().isShiftClick()) {
          Inventory clicked = event.getClickedInventory();
          if (clicked == event.getWhoClicked().getInventory()) {
              // The item is being shift clicked from the bottom to the top
              ItemStack clickedOn = event.getCurrentItem();
              if (clickedOn != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)) {
                  event.setCancelled(true);
              }
          }
      }
  }
  public void onInventoryClick2(InventoryClickEvent event) {
      Inventory clicked = event.getClickedInventory();
      if (clicked != event.getWhoClicked().getInventory()) { // Note: !=
          // The cursor item is going into the top inventory
          org.bukkit.inventory.ItemStack onCursor = event.getCursor();

          if (onCursor != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)) {
              event.setCancelled(true);
          }
      }
  }
  @EventHandler
  public void onInventoryDrag(InventoryDragEvent event) {
      @SuppressWarnings("unused")
    org.bukkit.inventory.ItemStack dragged = event.getOldCursor(); // This is the item that is being dragged

      if (event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)) {
          int inventorySize = event.getInventory().getSize(); // The size of the inventory, for reference

          // Now we go through all of the slots and check if the slot is inside our inventory (using the inventory size as reference)
          for (int i : event.getRawSlots()) {
              if (i < inventorySize) {
                  event.setCancelled(true);
                  break;
              }
          }
      }
  }
}

 

its working now but i have one and only problem right now my InventoryDragEvent is not working

Code:

      public void onInventoryDrag(InventoryDragEvent event) {
          @SuppressWarnings("unused")
        org.bukkit.inventory.ItemStack dragged = event.getOldCursor(); // This is the item that is being dragged

          if (dragged.getEnchantments() != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)) {
              int inventorySize = event.getInventory().getSize(); // The size of the inventory, for reference

              // Now we go through all of the slots and check if the slot is inside our inventory (using the inventory size as reference)
              for (int i : event.getRawSlots()) {
                  if (i < inventorySize) {
                      event.setCancelled(true);
                      break;
}
              }
          }
      }

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

PlayerInventory#getItemInMainHand() has the @NotNull annotation. However, as you said, the ItemMeta should be checked.

@vondalenocon4x Define "not working."
ItemStack#getEnchantments() has the @NotNull annotation, so your first check will never be false.

 

what should i do about it can you give me some example? TIA

 

@vondalenocon4x You can start by telling us what you want to do and what is not working. We can begin helping you from there.

 

the error was fixed but the problem is when i tried to drag the item with custom enchant it's not working.

i think there is a problem in my code here

Code:

      public void onInventoryDrag(InventoryDragEvent event) {
          @SuppressWarnings("unused")
        org.bukkit.inventory.ItemStack dragged = event.getOldCursor(); // This is the item that is being dragged

          if (dragged.getEnchantments() != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)) {
              int inventorySize = event.getInventory().getSize(); // The size of the inventory, for reference

              // Now we go through all of the slots and check if the slot is inside our inventory (using the inventory size as reference)
              for (int i : event.getRawSlots()) {
                  if (i < inventorySize) {
                      event.setCancelled(true);
                      break;
}
              }
          }
      }

the thing is i want the item with custom enchant prevent to put in chest and to other containers too.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

@vondalenocon4x
You need to provide more information that just that, you should include what your code is supposed to do, and probably also include what it's doing instead (add a breakpoint and step through the function).

I assume you're trying to make a custom enchantment so that an item can't be removed from your inventory. If that's the case then I think this line is wrong:

Code:

dragged.getEnchantments() != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)

getOldCursor is the item before it was being dragged, but getItemInMainHand is the item in the players hand (the equipped item in the hotbar), not the item being dragged.

 

yes your right im trying to make custom enchant to prevent moving it to players inventory. What should i change in this line

Code:

dragged.getEnchantments() != null && event.getWhoClicked().getInventory().getItemInMainHand().getItemMeta().hasEnchant((Enchantment)Main.undroppable)