* @return master + port, or null if server has been stopped
*/
public ServerName getMaster() {
ServerName masterServerName = null;
long previousLogTime = 0;
FServerStatusProtocol master = null;
while (keepLooping() && master == null) {
masterServerName = this.masterAddressManager.getMasterAddress();
if (masterServerName == null) {
if (!keepLooping()) {
// give up with no connection.