maintaining data in two parallel arrays is a nightmare. You'd do better by making a single object that can store both the String and the array associated with it. Then you could possibly store them in a map, using the String as the key. First check to see if it is already in the collection, and if so, 'combine' your arrays. If not, simply add it in.
There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors