Error when I try to pick a banned IP

Well guys, i trying to make a /banip /ipban example plugin, for that, i've created a .YML file to save all banned ip's.
The problem is, i can banip and save it normally, but when i try to pick that in a PlayerLoginEvent, he show a error in console... Someone can help-me?

ipBanCommand:

Code:

import Main.Main;
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 java.io.IOException;

public class BanIP implements CommandExecutor {

    public static String BanReason;
    public static String BanAuthor;
    public static String BannedIP;

    public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args){
        Player p = (Player) sender;

        String perm = "flash.ipban";
        String cmd1 = "IPBAN";
        String cmd2 = "BANIP";
        String motivo = "";
        String Author = p.getName();

        if(cmd.getName().equalsIgnoreCase(cmd1) || cmd.getName().equalsIgnoreCase(cmd2)){
            if(!p.hasPermission(perm)){
                p.sendMessage("§cVocê não tem permissão para executar esse comando!");
                return true;
            }
            if(args.length == 0){
                p.sendMessage("§3IPBAN  §cVocê precisa selecionar o jogador!");
                return true;
            }
            if(args.length == 1){
                p.sendMessage("§3IPBAN  §cSeu ban precisa ter um motivo!");
                return true;
            }
            if(args.length > 1){
                Player target = (Player) Bukkit.getServer().getPlayer(args[0]);
                String ip = target.getAddress().getAddress().getHostAddress();

                for(int i = 1; i < args.length; i++){
                    motivo = (motivo+args[i]+" ");
                }

                BanReason = motivo;
                BanAuthor = Author;
                BannedIP = ip;

                if(target == null){
                    p.sendMessage("§3IPBAN  §cO jogador precisa estar online!");
                    return true;
                }
                target.kickPlayer("§f§lFLASH§cMC"+"\n"+"§cVocê foi permanentemente banido de nosso servidor!"+"\n"+"§fMotivo: §c"+motivo+"\n"+"§fAutor: §c"+Author);
                Bukkit.broadcastMessage("§fO jogador §c"+target.getName()+" §ffoi banido por §c"+p.getName()+"§f Motivo: §c"+motivo);
                Main.ipbancfg.set(BannedIP, "");
                Main.ipbancfg.set(BannedIP+".MOTIVO", BanReason);
                Main.ipbancfg.set(BannedIP+".AUTOR", BanAuthor);
                try{
                    Main.ipbancfg.save(Main.IPbanned);
                }catch (IOException e){
                    e.printStackTrace();
                }
                return true;


            }
        }



        return false;
    }
}

Checking the ip in the YML file:

Code:

String ip = p.getAddress().getAddress().getHostAddress();

if(Main.ipbancfg.get(BanIP.BannedIP) == ip){
            e.disallow(PlayerLoginEvent.Result.KICK_BANNED, "§f§lFLASH§cMC"+"\n"+"§cVocê esta permanentemente banido de nosso servidor!"+"\n"+"§fMotivo: §c"+Main.ipbancfg.getString(BanIP.BannedIP+".MOTIVO")+"\n"+"§fAutor: §c"+Main.ipbancfg.getString(BanIP.BannedIP+".AUTOR"));
            return;
        }

[EDIT]

CONSOLE ERROR:

[19:59:14 ERROR]: Could not pass event PlayerLoginEvent to FlashMC v1.5
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:297) ~[craftbukkit.jar:git-Bukkit-33d5de3]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit.jar:git-Bukkit-33d5de3]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:501) [craftbukkit.jar:git-Bukkit-33d5de3]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:486) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.PlayerList.attemptLogin(PlayerList.java:409) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.LoginListener.b(LoginListener.java:69) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.LoginListener.c(LoginListener.java:41) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.NetworkManager.a(NetworkManager.java:150) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.ServerConnection.c(SourceFile:151) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.MinecraftServer.z(MinecraftServer.java:733) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.DedicatedServer.z(DedicatedServer.java:284) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.MinecraftServer.y(MinecraftServer.java:609) [craftbukkit.jar:git-Bukkit-33d5de3]
at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:517) [craftbukkit.jar:git-Bukkit-33d5de3]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_201]
Caused by: java.lang.NullPointerException
at Eventos.CheckPlayer.checkConnection(CheckPlayer.java:25) ~[?:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_201]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_201]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_201]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_201]
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:295) ~[craftbukkit.jar:git-Bukkit-33d5de3]
... 13 more

@KarimAKL

 

@idkG0D What is the error in the console?
EDIT: Also, to compare strings use '.equals()', not '=='.

 

The error is happening here:
at Eventos.CheckPlayer.checkConnection(CheckPlayer.java:25)
Go to the CheckPlayer class on line 25 - there is a null object there.
Post the code on line 25.
Mind posting the CheckPlayer class code and your Main class code?