无法导入任何 org.bukkit 库

I am making a spigot mod with using a spigot jar and running that and I cannot import anything from org.bukkit.

My plugin is supposed to give players random hearts when they join for the first time.

My code is:

import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.plugin.java.JavaPlugin;

import java.util.Random;

public class RandomHeartsPlugin extends JavaPlugin implements Listener {

    @Override
    public void onEnable() {
        getServer().getPluginManager().registerEvents(this, this);
    }

    @EventHandler
    public void onPlayerJoin(PlayerJoinEvent event) {
        Player player = event.getPlayer();
        int randomHearts = generateRandomHearts();
        player.setHealth(randomHearts);
        player.sendMessage("You have been given " + randomHearts + " extra hearts!");
    }

    private int generateRandomHearts() {
        Random random = new Random();
        // Generating a random number between 0 and 20 (inclusive)
        return random.nextInt(21);
    }
}

and I run it with the command:

javac plugins/RandomHeartsPlugin.java -cp bundler/libaries

I tried using -cp wiht other things but I still can't compile it, I get:

plugins\RandomHeartsPlugin.java:3: error: package org.bukkit.entity does not exist
import org.bukkit.entity.Player;
                        ^
plugins\RandomHeartsPlugin.java:4: error: package org.bukkit.event does not exist
import org.bukkit.event.EventHandler;
                       ^
plugins\RandomHeartsPlugin.java:5: error: package org.bukkit.event does not exist
import org.bukkit.event.Listener;
                       ^
plugins\RandomHeartsPlugin.java:6: error: package org.bukkit.event.player does not exist
import org.bukkit.event.player.PlayerJoinEvent;
                              ^
plugins\RandomHeartsPlugin.java:7: error: cannot find symbol
import org.bukkit.plugin.java.JavaPlugin;
                             ^
  symbol:   class JavaPlugin
  location: package org.bukkit.plugin.java
plugins\RandomHeartsPlugin.java:11: error: cannot find symbol
public class RandomHeartsPlugin extends JavaPlugin implements Listener {
                                        ^
  symbol: class JavaPlugin
plugins\RandomHeartsPlugin.java:11: error: cannot find symbol
public class RandomHeartsPlugin extends JavaPlugin implements Listener {
                                                              ^
  symbol: class Listener
plugins\RandomHeartsPlugin.java:19: error: cannot find symbol
    public void onPlayerJoin(PlayerJoinEvent event) {
                             ^
  symbol:   class PlayerJoinEvent
  location: class RandomHeartsPlugin
plugins\RandomHeartsPlugin.java:18: error: cannot find symbol
    @EventHandler
     ^
  symbol:   class EventHandler
  location: class RandomHeartsPlugin
plugins\RandomHeartsPlugin.java:13: error: method does not override or implement a method from a supertype
    @Override
    ^
plugins\RandomHeartsPlugin.java:15: error: cannot find symbol
        getServer().getPluginManager().registerEvents(this, this);
        ^
  symbol:   method getServer()
  location: class RandomHeartsPlugin
plugins\RandomHeartsPlugin.java:20: error: cannot find symbol
        Player player = event.getPlayer();
        ^
  symbol:   class Player
  location: class RandomHeartsPlugin
12 errors