CraftBlockData.java

    public static CraftBlockData fromData(IBlockData data) {
        Class<? extends CraftBlockData> craft = MAP.get(data.getBlock().getClass());
        if (craft == null) {
            craft = CraftBlockData.class;
        }

        CraftBlockData ret;
        try {
            ret = craft.getDeclaredConstructor(IBlockData.class).newInstance(data);
        } catch (ReflectiveOperationException ex) {
            throw new RuntimeException(ex);
        }

        return ret;
    }