There are current three crafting recipes added by this command block contraption.
1. Dirt Stick
2. Dirt Sword
3. Notch Sword
All of which are crafted in a custom 3x3 crafting table.

This works in single and multiplayer(just as long as command blocks are enabled.
There should be only one forge per world(more will result in duplication).
This will work in 1.10.x(Snapshots haven't been tested).