So i've just started modding minecraft as i'm more use to sponge so i'm trying to piece things together...can someone explain why 

@Mod("asuramagica")
public class Main 
{
	public static Main instance;
	public static String modid = "asuramagica";
	private static final Logger logger = LogManager.getLogger(modid);



	public Main() {


		
		
		instance = this;
		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::arrowNocked);
		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::setup);
		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::clientRegistries);
		
		MinecraftForge.EVENT_BUS.register(this);
		
		
	}

	public void arrowNocked(PlayerEvent.PlayerLoggedInEvent event)
	{
		System.out.println("Testing");
	}

	private static void init(final FMLServerAboutToStartEvent event){
		
	}

	private void setup(final FMLCommonSetupEvent event){
		logger.info("Setup method registered.");
	}
	
	private void clientRegistries(final FMLClientSetupEvent event){
		logger.info("clientRegistries method registered.");
	}
}

 

is not pushing out Testing to the console....when a Player joins the server? i've tried both this way and

@Mod("asuramagica")
public class Main 
{
	public static Main instance;
	public static String modid = "asuramagica";
	private static final Logger logger = LogManager.getLogger(modid);



	public Main() {


		
		
		instance = this;
		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::setup);
		FMLJavaModLoadingContext.get().getModEventBus().addListener(this::clientRegistries);
		
		MinecraftForge.EVENT_BUS.register(this);
		
		
	}
	@SubscribedEvent
	public static void arrowNocked(PlayerEvent.PlayerLoggedInEvent event)
	{
		System.out.println("Testing");
	}

	private static void init(final FMLServerAboutToStartEvent event){
		
	}

	private void setup(final FMLCommonSetupEvent event){
		logger.info("Setup method registered.");
	}
	
	private void clientRegistries(final FMLClientSetupEvent event){
		logger.info("clientRegistries method registered.");
	}
}

 

Thanks that solved it.  I'm still trying to figure out the whole server side client side portion....but i understood that i just simply needed to add a @SubscribedEvent to make 'Thanks' appear.