[1.12.2] Packet Crashes Client on Server [SOLVED]

[HalestormXV]

So a simple question. I followed this tutorial by McJty which utilizes the SimpleNetwork message setup. He uses MovingObjectPosition which I know has been changed to RayTraceResult so I made that change. But when I am on a server and press the Key Bind the client crashes with this: https://pastebin.com/Aje5pDik

 

It's crashing at line 38 of this class: https://pastebin.com/4x3hKbMd

 

Now I know from some past network usage on older versions, that usually Minecraft.getMinecraft() may not be the best thing to use since if I recall getMinecraft() is a bad function to call on a server (perhaps I am wrong). I am only guessing that it has to do with that because it works fine on SinglePlayer only. It only blows up like that if you do it while logged into a server. Insights? Correction that needs to be applied? Perhaps the tutorial was made for a different version of Forge and something else was changed that I was unaware of?

 

If you happen to need the PacketHandler itself, it is really small so I just pasted it.

 

public class PacketHandler
{
    private static int packetId = 0;

    public static SimpleNetworkWrapper INSTANCE = null;

    public PacketHandler() {
    }

    public static int nextID() {
        return packetId++;
    }

    public static void registerMessages(String channelName)
    {
        INSTANCE = NetworkRegistry.INSTANCE.newSimpleChannel(channelName);
        registerMessages();
    }

    public static void registerMessages() {
        // Register messages which are sent from the client to the server here:
        INSTANCE.registerMessage(PacketSendKey.Handler.class, PacketSendKey.class, nextID(), Side.SERVER);
    }
}

Edited February 10, 2018 by HalestormXV

[quadraxis]

That tutorial isn't really doing things quite right here.

 

Have two seperate constructors for your packet like so:

 

public PacketSendKey() {}

public PacketSendKey(BlockPos blockPos)
{
	this.blockPos = blockPos;
}

 

Then when you go to send this packet, get the mousever position from the client and pass it to the packet constructor yourself.

 

You can't reference client-sided code in the packet constructor as the packet also needs to be constructed on the server (so it can be passed to your packet handler).

[quadraxis]

Also read through the docs page if you haven't already.

[HalestormXV]

Fixed it, thanks. I thought something looked wrong with the tutorial since I have done similar things like this in the past and it just seemed off but I wasn't sure if something changed in 1.12.2 or something that I may have missed.

Edited February 10, 2018 by HalestormXV