DOBTprox.txt

@Mod.EventBusSubscriber
public class CommonProxy {
    public static Configuration config;
	public void preInit(FMLPreInitializationEvent e) {
		File directory = e.getModConfigurationDirectory();
        config = new Configuration(new File(directory.getPath(), "modtut.cfg"));
        Config.readConfig();
    }

    public void init(FMLInitializationEvent e) {
    }

    public void postInit(FMLPostInitializationEvent e) {
	    if (config.hasChanged()) {
        config.save();
    }

    @SubscribeEvent
    public static void registerBlocks(RegistryEvent.Register<Block> event) {
    }
	@SubscribeEvent
    public static void registerItems(RegistryEvent.Register<Item> event) {
        event.getRegistry().register(new FirstItem());
        
    }

    @SubscribeEvent
    public static void registerItems(RegistryEvent.Register<Item> event) {
    }
}


@Mod.EventBusSubscriber(Side.CLIENT)
public class ClientProxy extends CommonProxy {
    @Override
    public void preInit(FMLPreInitializationEvent e) {
        super.preInit(e);
    }

    @SubscribeEvent
    public static void registerModels(ModelRegistryEvent event) {
    }
}

public class ServerProxy extends CommonProxy {

}