code: private SecureRandom createSecureRandom() {
          SecureRandom result;
          try {
              result = SecureRandom.getInstance("SHA1PRNG");
          } catch (NoSuchAlgorithmException e) {
              result = new SecureRandom();
          }
  
          // Force seeding to take place.
          result.nextInt();
          return result;
      }
docs: Create a new random number generator instance we should use for generating session identifiers.