Hello. I'm working with SimpleNetworkWrapper and my mod should spawn entity when it receives message. Message receiving works great, but when i'm trying to spawn enitity, it doesn't do it.

Here's my Message.java:

import cpw.mods.fml.common.network.ByteBufUtils;
import cpw.mods.fml.common.network.simpleimpl.IMessage;
import cpw.mods.fml.common.network.simpleimpl.IMessageHandler;
import cpw.mods.fml.common.network.simpleimpl.MessageContext;
import io.netty.buffer.ByteBuf;
import net.minecraft.world.WorldServer;
import net.minecraftforge.common.DimensionManager;

public class Message implements IMessage{

private String text;

public Message() { }

public Message(String text) {
        this.text = text;
    }

@Override
public void fromBytes(ByteBuf buf) {
	text = ByteBufUtils.readUTF8String(buf);
}

@Override
public void toBytes(ByteBuf buf) {
	ByteBufUtils.writeUTF8String(buf, text);
}

 public static class Handler implements IMessageHandler<Message, IMessage> {
        
        @Override
        public IMessage onMessage(Message message, MessageContext ctx) {
            String[] action = message.text.split(" ");
            System.out.println(String.format("Recieved message %s.", message.text));
            if (action[0].equals("spawn")) {
            	
            	WorldServer world = null;
            	double x, y, z;
            	
            	for(WorldServer _world : DimensionManager.getWorlds()) {
            		if (_world.getWorldInfo().getWorldName().equals(action[1])) {
            			world = _world;
            		}
            		
        		CrystallEntity crystall = new CrystallEntity(world);

            		x = Double.valueOf(action[2]);
            		y = Double.valueOf(action[3]);
            		z = Double.valueOf(action[4]);
            		
            		crystall.setLocationAndAngles(x, y, z, 0.0F, 0.0F);
            		
            		System.out.println(String.format("Trying to spawn a Crystall at %d %d %d", x, y, z));
            		
            		world.spawnEntityInWorld(crystall);
            	}
            }
        	return null; // no response in this case
        }
        
 }
}

You cannot interact with the main Minecraft threads from the networking thread. See the warning at mcforge.readthedocs.org for more information.

Also don't implement IMessage and IMessageHandler in the same class file, you'll invariably mess something up.

Also don't implement IMessage and IMessageHandler in the same class file, you'll invariably mess something up.

 

I don't really agree with this. Implementing them both on a single class is a bad idea and can lead to confusion (which instance is the handler and which is the message?), but implementing one in a nested class of the other (like the OP has done) isn't likely to cause much confusion. You've still got two separate classes, but they're grouped together in one file instead of two.

 

To the OP: 1.7.10 is no longer supported here. You should update to 1.10.2.

I don't really agree with this. Implementing them both on a single class is a bad idea and can lead to confusion (which instance is the handler and which is the message?), but implementing one in a nested class of the other (like the OP has done) isn't likely to cause much confusion. You've still got two separate classes, but they're grouped together in one file instead of two.

 

Personally, I still think it helps to have the classes in different files.  There was another poster about a week ago who'd used the nested class structure and was having an issue that as soon as I suggested he use separate files he found and fixed his problem.