void _pickInitial() throws MongoException {
    if (_curAddress != null) return;

    // we need to just get a server to query for ismaster
    _pickCurrent();

    try {
      _logger.info("current address beginning of _pickInitial: " + _curAddress);

      DBObject im = isMasterCmd();
      if (_isMaster(im)) return;

      synchronized (_allHosts) {
        Collections.shuffle(_allHosts);
        for (ServerAddress a : _allHosts) {
          if (_curAddress == a) continue;

          _logger.info("remote [" + _curAddress + "] -> [" + a + "]");
          _set(a);

          im = isMasterCmd();
          if (_isMaster(im)) return;

          _logger.severe("switched to: " + a + " but isn't master");
        }

        throw new MongoException("can't find master");
      }
    } catch (Exception e) {
      _logger.log(Level.SEVERE, "can't pick initial master, using random one", e);
    }
  }
  private void _pickCurrent() throws MongoException {
    if (_allHosts == null)
      throw new MongoException(
          "got master/slave issue but not in master/slave mode on the client side");

    synchronized (_allHosts) {
      Collections.shuffle(_allHosts);
      for (int i = 0; i < _allHosts.size(); i++) {
        ServerAddress a = _allHosts.get(i);
        if (a == _curAddress) continue;

        if (_curAddress != null) {
          _logger.info("switching from [" + _curAddress + "] to [" + a + "]");
        }

        _set(a);
        return;
      }
    }

    throw new MongoException("couldn't find a new host to swtich too");
  }