In java, how to check if a list have the same element in a list?

String[] keywordsArray = { "IF", "WRITE", "READ", "RETURN", "BEGIN", "END", "MAIN"}; Set keywords = new HashSet(); for (String s : keywordsArray) {; keywords.add(s); }

String token="BACK";

i want to check if the token is in the keyworks list, but i dont know how, how to do that?