Solved java.lang.ClassCastException: gui.PunishGUI cannot be cast to org.bukkit.command.CommandExecutor

I dont know how to fix this problem someone pls help

Error:

Code:

[00:16:13 ERROR]: Error occurred while enabling GLEssentials v1.0 (Is it up to date?)
java.lang.ClassCastException: gui.PunishGUI cannot be cast to org.bukkit.command.CommandExecutor
    at main.Main.onEnable(Main.java:19) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[craftbukkit.jar:git-Bukkit-b105298]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:332) [craftbukkit.jar:git-Bukkit-b105298]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:404) [craftbukkit.jar:git-Bukkit-b105298]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:341) [craftbukkit.jar:git-Bukkit-b105298]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:313) [craftbukkit.jar:git-Bukkit-b105298]
    at net.minecraft.server.v1_8_R3.MinecraftServer.s(MinecraftServer.java:406) [craftbukkit.jar:git-Bukkit-b105298]
    at net.minecraft.server.v1_8_R3.MinecraftServer.k(MinecraftServer.java:370) [craftbukkit.jar:git-Bukkit-b105298]
    at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:325) [craftbukkit.jar:git-Bukkit-b105298]
    at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:235) [craftbukkit.jar:git-Bukkit-b105298]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:503) [craftbukkit.jar:git-Bukkit-b105298]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_171]

Main:

Code:

package main;

import gui.PunishGUI;

import org.bukkit.ChatColor;
import org.bukkit.command.CommandExecutor;
import org.bukkit.plugin.java.JavaPlugin;

import commands.GMC;
import commands.GMS;

public class Main extends JavaPlugin {

    public void onEnable() {
        System.out.println(ChatColor.BLUE + "Essentials> " + ChatColor.GRAY + "Plugin has been: " + ChatColor.GREEN + "ACTIVATED.");
            //commands
                this.getCommand("gmc").setExecutor((CommandExecutor) new GMC());
                this.getCommand("gms").setExecutor((CommandExecutor) new GMS());
                this.getCommand("p").setExecutor((CommandExecutor) new PunishGUI());
       
        }
    public void Disable() {
        System.out.println(ChatColor.BLUE + "Essentials> " + ChatColor.GRAY + "Plugin has been: " + ChatColor.RED + "DEACTIVATED.");
    }
}

PunishGUI:

Code:

package gui;

import org.bukkit.Bukkit;
import org.bukkit.entity.Player;
import org.bukkit.inventory.Inventory;

public class PunishGUI {

    public static Inventory punishGUI = Bukkit.createInventory(null, 54, "hi");
   
    public PunishGUI() {
       
    }
   
    public static boolean openGUI(Player player) {
       
        player.openInventory(punishGUI);
       
       
        punishGUI.setItem(0, null);
        punishGUI.setItem(1, null);
        punishGUI.setItem(2, null);
        punishGUI.setItem(3, null);
        punishGUI.setItem(4, null);
        punishGUI.setItem(5, null);
        punishGUI.setItem(6, null);
        punishGUI.setItem(7, null);
        punishGUI.setItem(8, null);
        return true;
    }
   
}

 

@GodzillaFlame42
To add onto what Tim posted, you should not cast the object, you should let PunishGUI implement CommandExecutor.

 

@timtower @Zombie_Striker
i dont know whats wrong now. there are no errors but it wont open the gui itself.

PunishGUI:

Code:

package gui;

import org.bukkit.Bukkit;
import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.inventory.Inventory;

public class PunishGUI implements CommandExecutor {

    public static Inventory punishGUI = Bukkit.createInventory(null, 54, "test");
   
        public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
            Player player = (Player) sender;
            if (sender instanceof Player) {
            }
            return false;
        }
       
        public PunishGUI() {
           
        }
   
    public static boolean openGUI(Player player) {
       
        player.openInventory(punishGUI);
       
       
        punishGUI.setItem(0, null);
        punishGUI.setItem(1, null);
        punishGUI.setItem(2, null);
        punishGUI.setItem(3, null);
        punishGUI.setItem(4, null);
        punishGUI.setItem(5, null);
        punishGUI.setItem(6, null);
        punishGUI.setItem(7, null);
        punishGUI.setItem(8, null);
        return true;

    }
   
}

 

@GodzillaFlame42
You never call openGUI in the onCommand.

 

@Zombie_Striker
ty