code: private User addUser(String userName)
      {
          User user = new User();
          PersonalDetail personalDetail = new PersonalDetail(userName, userName + "Password", "Single");
          user.setUserId(userName);
          user.setEmailId(userName + "@" + userName + ".com");
          user.setFirstName(userName);
          user.setLastName(userName);
          user.setTweets(new HashSet<Tweets>());
          user.setPersonalDetail(personalDetail);
          return user;
      }
docs: /*
  Populates user instance for provided userName attribute.