Solved Issues with Listeners

Hello!
I'm having issues with my plugin that I am coding. Any help would be appreciated. Nothing that I have asked to happen has happened.

Code:

package me.admin.myrescb;

import java.util.ArrayList;
import java.util.List;

import org.bukkit.entity.Entity;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.EntityDamageByEntityEvent;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.event.player.PlayerQuitEvent;
import org.bukkit.plugin.java.JavaPlugin;

public class Main extends JavaPlugin implements Listener{
   
    List<Player> playerfirstJoin = new ArrayList<Player>();
   
    public void onEnable(){
       
        getLogger().info("MyresCB has loaded succesfully!");
       
        getServer().getPluginManager().registerEvents(this, this);
       
       
    }
    public void onDisable(){
       
    }
   
    @EventHandler
    public void onPlayerDamage(EntityDamageByEntityEvent event){
           
        Entity entity = event.getEntity();
       
            if(entity.getType().equals(EntityType.PLAYER)){
                if(playerfirstJoin.contains(entity.getName())){
                if(event.getDamager() instanceof Player){
                    event.setCancelled(true);
                }
                       
                }
               
            }
               
                }
       
           
           
               
           
   
    @EventHandler
        public void onPlayerJoin(PlayerJoinEvent event){
       
        Player p = event.getPlayer();
       
            if(!(p.hasPlayedBefore())){
                playerfirstJoin.add(p);
            }
        }
           
   
       
    @EventHandler
    public void onPlayerQuit(PlayerQuitEvent event){
       
        Player p = event.getPlayer();
       
        if(playerfirstJoin.contains(p)){
            playerfirstJoin.remove(p);
        }else{
           
        }
    }
   
}

 

What's actually wrong?Error on startup?Maybe you could post a log?

 

@Minterrr
Exactly what doesn't happen?

Also, don't log that your plugin enables, bukkit does this for you. Your onDisable method also does nothing and can be removed.

 

If the player hasnt joined before, they either arent added to the ArrayList or the damage event isnt canceled.

@CaptainMike2828

No errors are logged in console

 

@Minterrr
What happens if you put a print statement in the event handler methods?

 

Don't log your own plugin. bukkit does this for you. Remove this lne.

This method does nothing. Delete it.

Fix your formatting. If you have to, use CTRL+Shift+F if you're using eclipse.

1# Use == when comparing enum values.
2# Be consistent with the way you check what entities are.

This does nothing. Remove it.

Are you sure this will be true? So far, your code looks like it should work. Are you sure the player has been added to the array?

 

Let me show you what I have now. And I don't think the player is being added to the arraylist. How would I check? I also thought it should work, I don't know why it isn't.

Code:

package me.admin.myrescb;

import java.util.ArrayList;
import java.util.List;

import org.bukkit.entity.Entity;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.EntityDamageByEntityEvent;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.event.player.PlayerQuitEvent;
import org.bukkit.plugin.java.JavaPlugin;

public class Main extends JavaPlugin implements Listener {

    List<Player> playerfirstJoin = new ArrayList<Player>();

    public void onEnable() {

        getServer().getPluginManager().registerEvents(this, this);

    }

    @EventHandler

    public void onPlayerDamage(EntityDamageByEntityEvent event) {

        Entity entity = event.getEntity();

        if (entity.getType() == EntityType.PLAYER) {
            if (playerfirstJoin.contains(entity.getName())) {
                if (event.getDamager() instanceof Player) {
                    event.setCancelled(true);
                }

            }

        }

    }

    @EventHandler
    public void onPlayerJoin(PlayerJoinEvent event) {

        Player p = event.getPlayer();

        if (!(p.hasPlayedBefore())) {
            playerfirstJoin.add(p);

            ;
        }
    }

    @EventHandler
    public void onPlayerQuit(PlayerQuitEvent event) {

        Player p = event.getPlayer();

        if (playerfirstJoin.contains(p)) {
            playerfirstJoin.remove(p);
        }

    }
}

 

@Minterrr
Print a message to console whenever you add an entry to the list.

 

@AlvinB

 

@Minterrr
Alright, that works, try putting a print statement in the EntityDamageByEntityEvent

 

@AlvinB nothing came up in console

 

@Minterrr

Here's the problem; You're putting in a Player instance, and trying to see if it contains a String. The object you store has to be consistent, and I would highly recommend changing the collection type to a UUID instead of a player. Since storing players can create memory leaks and players can change their names, UUIDs are the only thing that stays the same.

 

I am not familiar with using UUID's could you please show me how to do it?

@Zombie_Striker

 

@Minterrr Sure, here.

 

@Minterrr
To change your collection to store UUIDs, use the following

Code:

List<UUID> ......

To get player's UUIDs

Code:

player.getUniqueID()

 

@Zombie_Striker

I have changed it to UUID but it still isn't working. No errors in console...

Code:

package me.admin.myrescb;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

import org.bukkit.Bukkit;
import org.bukkit.entity.Entity;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.entity.EntityDamageByEntityEvent;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.event.player.PlayerQuitEvent;
import org.bukkit.plugin.java.JavaPlugin;

public class Main extends JavaPlugin implements Listener {

    List<UUID> playerfirstJoin = new ArrayList<UUID>();

    public void onEnable() {

        getServer().getPluginManager().registerEvents(this, this);

    }

    @EventHandler

    public void onPlayerDamage(EntityDamageByEntityEvent event) {

        Entity entity = event.getEntity();

        if (entity.getType() == EntityType.PLAYER) {
            if (playerfirstJoin.contains(entity.getName())) {
                event.setCancelled(true);
            }

        }

    }

    @EventHandler
    public void onPlayerJoin(PlayerJoinEvent event) {

        Player p = event.getPlayer();
        UUID id = p.getUniqueId();

        if (!(p.hasPlayedBefore())) {
            playerfirstJoin.add(id);

        }
    }

    @EventHandler
    public void onPlayerQuit(PlayerQuitEvent event) {

        Player p = event.getPlayer();
        UUID id = p.getUniqueId();
        if (playerfirstJoin.contains(id)) {
            playerfirstJoin.remove(id);
        }

    }
}

 

You still have not changed this line. Replace it with this:

 

@Zombie_Striker
Well noticed! Thanks sooo much! Working properly now