Reads come from nearest node.
Reads come only through the Primary
Reads come from Secondary servers (equiv of old SlaveOK)
Reads come from secondary if available, otherwise from primary
ReadPreference which reads nearest node respective of tags
ReadPreference which reads primary if available, otherwise a secondary respective of tags.
ReadPreference with reads primary if available
ReadPreference which returns secondary respective of tags
ReadPreference which reads secondary if available respective of tags, otherwise from primary irrespective of tags
Helper class for creating ReadPreference instances
2.2
JReadPreference