Generate random password

RandomPassword.java

    public class RandomPassword {
        private static String generateRandomPassword() {

            Random random = new Random();
            char start = characters.charAt(Math.floorMod(random.nextInt(), characters.length()));

            List<Character> chars = new ArrayList<>();
            for (int i = 0; i < 5; i++) {
                chars.add(characters.charAt(Math.floorMod(random.nextInt(), characters.length())));
            }
            chars.add(numeric.charAt(Math.floorMod(random.nextInt(), numeric.length())));
            chars.add(specialCharacters.charAt(Math.floorMod(random.nextInt(), specialCharacters.length())));

            Collections.shuffle(chars);

            String lastChars = StringUtils.join(chars, "");
            return start + lastChars;
        }
    }