How to separate a string into multiple smaller strings?

I'm creating a Dungeon Management System for my mod, and part of it is "linking" dungeon-related blocks like teleporters, etc. to the main Dungeon Manager block. The user would enter the coordinates of a block they want to connect into a textfield in a format like this:   x,y,z   I'm unsure how to separate this string into three smaller strings, using the commas as dividers. Any help would be greatly appreciated.