2. Use events

In the API, you can use following events:

APICraftItemEvent - this event is called when the player craft a item in the 5x5 workbench

APICreateRecipeEvent - this event is called when the player create a custom recipe

Every event have following methods:

Player getPlayer() - to get the handle player ARecipe getRecipe() - to get the recipe

Use this event, who all events in the spigotapi