[1.7.10] Crash on server start-up due to custom packets

[M4thG33k 0]

Greetings! I've received this crash report from someone who's been using my mod and I can't seem to pinpoint the actual source of the crash: http://pastebin.com/YQ91FgMM

 

From my understanding, the crash is happening when Forge is attempting to register my packet classes. The interesting thing is, this crash just recently appeared. I was fixing other bugs that were found, and then this crash crept in, which I find extremely odd. If there are any ideas as to what the problem could be (besides "you're attempting to use client-only classes on the server" since I can see that much), I would appreciate it.

 

Here's the line that I can trace back to from the crash report that is apparently causing the issue: https://goo.gl/fDL8OZ

 

Thanks in advance!

[diesieben07 6680]

Your message handlers are directly referencing client-only classes. You can't do that.

[M4thG33k 0]

Would it be possible for you to tell me which client-only classes I'm using? I know I'm using EntityFX in my code, but I thought that I was providing enough checks to make sure that all of that code is only being run on the client side. I suppose I'm still not fully understanding how packets are supposed to work (despite reading quite a few tutorials)...

[diesieben07 6680]

E.g. Minecraft.class is client only.

It doesn't matter that you are checking. The server will load both your IMessage and your IMessageHandler class, therefor nothing in that class can reference client-only code. Your IMessageHandler has a reference to the class Minecraft in it, therefor the server will crash.

[M4thG33k 0]

Ok, so is there a "proper way" to have the packet handler get a Minecraft world instance, then? I can't pass it in to the packet at all, but the packet should know what world it ends up in, right?

[diesieben07 6680]

Make a method in your proxy class that throws an exception on the server (it will never be called there) and does the stuff that your packet handler does now on the client. Then call that method from your packet handler.

[Ernio 598]

Get world via proxy.

 

In Common:

public World getClientWorld() { return null; }

In Client:

public World getClientWorld() {return Minecraft.getMinecraft().theWorld; }

 

EDIT

Dammit, he was faster

[M4thG33k 0]

All right, thanks to both of you! This makes perfect sense (even before seeing Ernio's code haha). I will attempt to put this into practice soon. Thanks for the quick responses!