@Override
  public boolean AddOneFriend(String sourceUserName, String targetUserName) {
    // TODO Auto-generated method stub

    ScholarUser targetUser = scholarUserDao.getScholarUserByName(targetUserName);
    if (targetUser == null) return false;
    ScholarUser sourceUser = scholarUserDao.getScholarUserByName(sourceUserName);
    return scholarUserDao.addOneUserForUser(sourceUser, targetUser);
  }