In both here and set_itemmeta, you have the same string, which is subject to changing as things are added. You should move this string to a single private static final String variable, and use that in both places, instead of copy/pasting. Btw, if you ever find yourself copy/pasting (not copy pasting, then making changes, as if the paste were a template) you should STRONGLY rethink what you're doing, and see if you can condense that into a function or something.