private MyPacketListener listener;

public void register() {
  listener = new MyPacketListener();
  Protocolize.listenerProvider().registerListener(listener);
}

public void unregister() {
  Protocolize.listenerProvider().unregisterListener(listener);
}

public class MyPacketListener extends AbstractPacketListener<Packet> {  
 
  public MyPacketListener() {  
    super(Packet.class, Direction.DOWNSTREAM, 0);  
  }  
 
  @Override  
  public void packetReceive(PacketReceiveEvent<Packet> event) {  
    // do something
    }  
  }  
}

private AbstractPacketListener<Packet> listener;

public void register() {
  listener = Protocolize.listenerProvider().register(Packet.class, Direction.DOWNSTREAM).onReceive(event -> {
    // do something
  });
}

public void unregister() {
  Protocolize.listenerProvider().unregister(listener);
}

ProtocolizePlayer player;
Object packet;
player.sendPacket(packet);
player.sendPacket(packet, Protocol.CONFIGURATION);

ProtocolizePlayer player;
Protocol decoderProtocol = player.decoderProtocol();
Protocol encoderProtocol = player.encoderProtocol();