So, I am trying to access the forge registry for all potions, specifically to apply a random one when a food is eaten. But, I am unclear on what the difference between ForgeRegistries.POTIONS.getValues() and .getEntries is. And when I copy the list from either and try to get the ID from that potion, by getIdFromPotion(potions.get(0)) (I'm am still unfamiliar with lists in java in case I am not even using list methods right, they are a little different from other languages' lists), it gives me an error The method getIdFromPotion(Potion) is undefined for the type *insert my class here, it's not relevant I think* But, the method DOES use Potion, if I am not mistaken here? Why would it give me that error? And is there an easier way to do what I am doing?

Can you post the whole class? Don't do things like *insert my class here*, it actually makes it harder to figure out what your problem is.

If you look at the method signatures in IForgeRegistry, you'll see that IForgeRegistry#getValues returns a List<V> (i.e. a collection of all values in the registry) whereas IForgeRegistry#getEntries returns a Set<Map.Entry<ResourceLocation, V>> (i.e. a collection of all name-value pairs in the registry).

 

There are very few areas where you need to use numeric IDs, they should be avoided wherever possible as they're automatically assigned and different for each save. You generally want to use the objects directly or use registry names if that's not possible.

 

If you tell us what you're trying to do, we can tell you how to do it.

He already explained what he's trying to do, he just want to randomly pick from all registered potions and apply it when a certain food item is eaten.

 

So I think he should use the getValues() then pick random number based on the list size and get the element based on that index.