@Mod.EventHandler
  public void preInit(FMLPreInitializationEvent event) {

    GameRegistry.registerBlock(blockLeafAir, "BlockLeafAir");

    ConfigurationHandler.init(event.getSuggestedConfigurationFile());
  }
  @EventHandler
  public void preInit(FMLPreInitializationEvent event) {
    logger = event.getModLog();
    if (event.getSide() == Side.CLIENT) isServer = false;
    else isServer = true;

    // Loads configuration
    config = new ConfigurationHandler();
    FMLCommonHandler.instance().bus().register(config);
    config.init(event.getSuggestedConfigurationFile());

    // registers channel handler
    ChannelHandler.init();

    // Register event handlers
    MinecraftForge.EVENT_BUS.register(ServerTickHandler.instance);
    FMLCommonHandler.instance().bus().register(ServerTickHandler.instance);
    if (event.getSide().isClient()) {
      MinecraftForge.EVENT_BUS.register(ClientTickHandler.instance);
      FMLCommonHandler.instance().bus().register(ClientTickHandler.instance);
    }
    NetworkRegistry.INSTANCE.registerGuiHandler(instance, proxy);
    CrossModLoader.preinit();
  }