HopperFilter (Whitelist & Blacklist)

Hopperfilter is an easy plugin to get more control over hoppers. You are already able to make filters in minecraft, but with this plugin it will be as easy as clicking a hopper and selecting the item.

How to use:
Right click a hopper while shifting to access it's "Inventory". While you are in this screen you can click any item in your inventory and it'll be added to the the whitelist list.

Left click a hopper while shifting to change the mode of the hopper. There are 2 modes: Whitelist and Blacklist. Whitelist makes it so only those items can flow through. Blacklist makes it so those items aren't able to flow through.