how to get random string value from list - android

i have few youtube api keys for my android project. eg :

YOUTUBE_API_KEY1 = XXXXXXXXXXX
     YOUTUBE_API_KEY2 = BBBBBBBBBBB
     YOUTUBE_API_KEY3 = NNNNNNNNNNN

and i want that my String YOUTUBE_API_KEY = random key from the keys list.

how can i do it? thanks