Package com.mongodb

Class ReadPreference

    • Method Detail

      • isSlaveOk

        public abstract boolean isSlaveOk​()
        True if this read preference allows reading from a secondary member of a replica set.
        Returns:
        if reading from a secondary is ok
      • getName

        public abstract String getName​()
        Gets the name of this read preference.
        Returns:
        the name
      • toDocument

        public abstract BsonDocument toDocument​()
        Gets a document representing this read preference in the wire protocol.
        Returns:
        the document
      • choose

        public final List<ServerDescription> choose​(ClusterDescription clusterDescription)
        Chooses the servers from the given cluster than match this read preference.
        Parameters:
        clusterDescription - the cluster description
        Returns:
        a list of matching server descriptions, which may be empty but may not be null
      • primary

        public static ReadPreference primary​()
        Gets a read preference that forces read to the primary.
        Returns:
        ReadPreference which reads from primary only
      • primaryPreferred

        public static ReadPreference primaryPreferred​()
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary.
        Returns:
        ReadPreference which reads primary if available.
      • secondary

        public static ReadPreference secondary​()
        Gets a read preference that forces reads to a secondary.
        Returns:
        ReadPreference which reads secondary.
      • secondaryPreferred

        public static ReadPreference secondaryPreferred​()
        Gets a read preference that forces reads to a secondary if one is available, otherwise to the primary.
        Returns:
        ReadPreference which reads secondary if available, otherwise from primary.
      • nearest

        public static ReadPreference nearest​()
        Gets a read preference that forces reads to a primary or a secondary.
        Returns:
        ReadPreference which reads nearest
      • primaryPreferred

        public static ReadPreference primaryPreferred​(long maxStaleness,
                                                      TimeUnit timeUnit)
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary.
        Parameters:
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads primary if available.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondary

        public static ReadPreference secondary​(long maxStaleness,
                                               TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary that is less stale than the given maximum.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondaryPreferred

        public static ReadPreference secondaryPreferred​(long maxStaleness,
                                                        TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary that is less stale than the given maximumm if one is available, otherwise to the primary.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        *
        Parameters:
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary if available, otherwise from primary.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • nearest

        public static ReadPreference nearest​(long maxStaleness,
                                             TimeUnit timeUnit)
        Gets a read preference that forces reads to a primary or a secondary that is less stale than the given maximum.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads nearest
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • primaryPreferred

        public static TaggableReadPreference primaryPreferred​(TagSet tagSet)
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary with the given set of tags.
        Parameters:
        tagSet - the set of tags to limit the list of secondaries to.
        Returns:
        ReadPreference which reads primary if available, otherwise a secondary respective of tags.\ * @since 2.13
      • secondary

        public static TaggableReadPreference secondary​(TagSet tagSet)
        Gets a read preference that forces reads to a secondary with the given set of tags.
        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        Returns:
        ReadPreference which reads secondary respective of tags.
        Since:
        2.13
      • secondaryPreferred

        public static TaggableReadPreference secondaryPreferred​(TagSet tagSet)
        Gets a read preference that forces reads to a secondary with the given set of tags, or the primary is none are available.
        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        Returns:
        ReadPreference which reads secondary if available respective of tags, otherwise from primary irrespective of tags.
        Since:
        2.13
      • nearest

        public static TaggableReadPreference nearest​(TagSet tagSet)
        Gets a read preference that forces reads to the primary or a secondary with the given set of tags.
        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        Returns:
        ReadPreference which reads nearest node respective of tags.
        Since:
        2.13
      • primaryPreferred

        public static TaggableReadPreference primaryPreferred​(TagSet tagSet,
                                                              long maxStaleness,
                                                              TimeUnit timeUnit)
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary with the given set of tags that is less stale than the given maximum.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSet - the set of tags to limit the list of secondaries to.
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads primary if available, otherwise a secondary respective of tags.\ * @since 3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondary

        public static TaggableReadPreference secondary​(TagSet tagSet,
                                                       long maxStaleness,
                                                       TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary with the given set of tags that is less stale than the given maximum.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary respective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondaryPreferred

        public static TaggableReadPreference secondaryPreferred​(TagSet tagSet,
                                                                long maxStaleness,
                                                                TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary with the given set of tags that is less stale than the given maximum, or the primary is none are available.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        *
        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary if available respective of tags, otherwise from primary irrespective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • nearest

        public static TaggableReadPreference nearest​(TagSet tagSet,
                                                     long maxStaleness,
                                                     TimeUnit timeUnit)
        Gets a read preference that forces reads to the primary or a secondary with the given set of tags that is less stale than the given maximum.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSet - the set of tags to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads nearest node respective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • primaryPreferred

        public static TaggableReadPreference primaryPreferred​(List<TagSet> tagSetList)
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary with one of the given sets of tags. The driver will look for a secondary with each tag set in the given list, stopping after one is found, or failing if no secondary can be found that matches any of the tag sets in the list.
        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        Returns:
        ReadPreference which reads primary if available, otherwise a secondary respective of tags.
        Since:
        2.13
      • secondary

        public static TaggableReadPreference secondary​(List<TagSet> tagSetList)
        Gets a read preference that forces reads to a secondary with one of the given sets of tags. The driver will look for a secondary with each tag set in the given list, stopping after one is found, or failing if no secondary can be found that matches any of the tag sets in the list.
        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        Returns:
        ReadPreference which reads secondary respective of tags.
        Since:
        2.13
      • secondaryPreferred

        public static TaggableReadPreference secondaryPreferred​(List<TagSet> tagSetList)
        Gets a read preference that forces reads to a secondary with one of the given sets of tags. The driver will look for a secondary with each tag set in the given list, stopping after one is found, or the primary if none are available.
        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        Returns:
        ReadPreference which reads secondary if available respective of tags, otherwise from primary irrespective of tags.
        Since:
        2.13
      • nearest

        public static TaggableReadPreference nearest​(List<TagSet> tagSetList)
        Gets a read preference that forces reads to the primary or a secondary with one of the given sets of tags. The driver will look for a secondary with each tag set in the given list, stopping after one is found, or the primary if none are available.
        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        Returns:
        ReadPreference which reads nearest node respective of tags.
        Since:
        2.13
      • primaryPreferred

        public static TaggableReadPreference primaryPreferred​(List<TagSet> tagSetList,
                                                              long maxStaleness,
                                                              TimeUnit timeUnit)
        Gets a read preference that forces reads to the primary if available, otherwise to a secondary with one of the given sets of tags that is less stale than the given maximum.

        The driver will look for a secondary with each tag set in the given list, stopping after one is found, or failing if no secondary can be found that matches any of the tag sets in the list.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads primary if available, otherwise a secondary respective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondary

        public static TaggableReadPreference secondary​(List<TagSet> tagSetList,
                                                       long maxStaleness,
                                                       TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary with one of the given sets of tags that is less stale than the given maximum.

        The driver will look for a secondary with each tag set in the given list, stopping after one is found, or failing if no secondary can be found that matches any of the tag sets in the list.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary respective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • secondaryPreferred

        public static TaggableReadPreference secondaryPreferred​(List<TagSet> tagSetList,
                                                                long maxStaleness,
                                                                TimeUnit timeUnit)
        Gets a read preference that forces reads to a secondary with one of the given sets of tags that is less stale than the given maximum.

        The driver will look for a secondary with each tag set in the given list, stopping after one is found, or the primary if none are available.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads secondary if available respective of tags, otherwise from primary irrespective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • nearest

        public static TaggableReadPreference nearest​(List<TagSet> tagSetList,
                                                     long maxStaleness,
                                                     TimeUnit timeUnit)
        Gets a read preference that forces reads to the primary or a secondary with one of the given sets of tags that is less stale than the given maximum.

        The driver will look for a secondary with each tag set in the given list, stopping after one is found, or the primary if none are available.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        tagSetList - the list of tag sets to limit the list of secondaries to
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        ReadPreference which reads nearest node respective of tags.
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)
      • valueOf

        public static ReadPreference valueOf​(String name)
        Creates a read preference from the given read preference name.
        Parameters:
        name - the name of the read preference
        Returns:
        the read preference
      • valueOf

        public static TaggableReadPreference valueOf​(String name,
                                                     List<TagSet> tagSetList)
        Creates a taggable read preference from the given read preference name and list of tag sets.
        Parameters:
        name - the name of the read preference
        tagSetList - the list of tag sets
        Returns:
        the taggable read preference
        Since:
        2.13
      • valueOf

        public static TaggableReadPreference valueOf​(String name,
                                                     List<TagSet> tagSetList,
                                                     long maxStaleness,
                                                     TimeUnit timeUnit)
        Creates a taggable read preference from the given read preference name, list of tag sets, and max allowable staleness of secondaries.

        The driver estimates the staleness of each secondary, based on lastWriteDate values provided in server isMaster responses, and selects only those secondaries whose staleness is less than or equal to maxStaleness.

        Parameters:
        name - the name of the read preference
        tagSetList - the list of tag sets
        maxStaleness - the max allowable staleness of secondaries. The minimum value is either 90 seconds, or the heartbeat frequency plus 10 seconds, whichever is greatest.
        timeUnit - the time unit of maxStaleness
        Returns:
        the taggable read preference
        Since:
        3.4
        See Also:
        TaggableReadPreference.getMaxStaleness(TimeUnit)