InvisibleFrame.java

package tk.orzo.spigot.test;

import org.bukkit.Material;
import org.bukkit.NamespacedKey;
import org.bukkit.craftbukkit.v1_16_R3.entity.CraftEntity;
import org.bukkit.craftbukkit.v1_16_R3.inventory.CraftItemStack;
import org.bukkit.entity.EntityType;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.hanging.HangingBreakByEntityEvent;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.ShapedRecipe;
import org.bukkit.plugin.java.JavaPlugin;

import net.minecraft.server.v1_16_R3.NBTTagByte;
import net.minecraft.server.v1_16_R3.NBTTagCompound;

public class InvisibleFrame implements Listener {

    private JavaPlugin plugin;

    public InvisibleFrame(JavaPlugin plugin) {
        this.plugin = plugin;
    }

    @EventHandler
    public void onFrameBreak(HangingBreakByEntityEvent e) {
        if (e.getEntity().getType() == EntityType.ITEM_FRAME) {
            net.minecraft.server.v1_16_R3.Entity nmsEntity = ((CraftEntity) e.getEntity()).getHandle();
            NBTTagCompound compound = new NBTTagCompound();
            nmsEntity.d(compound);

            if (compound.getBoolean("Invisible")) {
                e.setCancelled(true);
                e.getEntity().getLocation().getWorld().dropItem(e.getEntity().getLocation(), getItemStack());
                e.getEntity().remove();
            }
        }
    }

    public ShapedRecipe getRecipe() {
        NamespacedKey key = new NamespacedKey(plugin, "InvisibleItemframe");
        ShapedRecipe r = new ShapedRecipe(key , getItemStack());
        r.shape("   ", " I ", "   ");
        r.setIngredient( 'I', Material.ITEM_FRAME);
        return r;
    }

    public ItemStack getItemStack() {
        ItemStack item = new ItemStack(Material.ITEM_FRAME);
        net.minecraft.server.v1_16_R3.ItemStack nmsItem = CraftItemStack.asNMSCopy(item);
        NBTTagCompound compound = new NBTTagCompound();


        NBTTagCompound entityTag = new NBTTagCompound();
        entityTag.set("Invisible", NBTTagByte.a(true));
        compound.set("EntityTag", entityTag);


        nmsItem.setTag(compound);


        return CraftItemStack.asBukkitCopy(nmsItem);
    }

}