Package org.redisson

Class RedissonGeo<V>

    • Method Detail

      • addAsync

        public RFuture<Long> addAsync​(double longitude,
                                      double latitude,
                                      V member)
        Description copied from interface: RGeoAsync
        Adds geospatial member.
        Specified by:
        addAsync in interface RGeoAsync<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set, not including elements already existing for which the score was updated
      • add

        public long add​(double longitude,
                        double latitude,
                        V member)
        Description copied from interface: RGeo
        Adds geospatial member.
        Specified by:
        add in interface RGeo<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set, not including elements already existing for which the score was updated
      • add

        public long add​(GeoEntry... entries)
        Description copied from interface: RGeo
        Adds geospatial members.
        Specified by:
        add in interface RGeo<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set, not including elements already existing for which the score was updated
      • addAsync

        public RFuture<Long> addAsync​(GeoEntry... entries)
        Description copied from interface: RGeoAsync
        Adds geospatial members.
        Specified by:
        addAsync in interface RGeoAsync<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set, not including elements already existing for which the score was updated
      • addIfExists

        public Boolean addIfExists​(double longitude,
                                   double latitude,
                                   V member)
        Description copied from interface: RGeo
        Adds geospatial member only if it's already exists.

        Requires Redis 6.2.0 and higher.

        Specified by:
        addIfExists in interface RGeo<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set
      • addIfExists

        public long addIfExists​(GeoEntry... entries)
        Description copied from interface: RGeo
        Adds geospatial members only if it's already exists.

        Requires Redis 6.2.0 and higher.

        Specified by:
        addIfExists in interface RGeo<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set
      • addIfExistsAsync

        public RFuture<Boolean> addIfExistsAsync​(double longitude,
                                                 double latitude,
                                                 V member)
        Description copied from interface: RGeoAsync
        Adds geospatial member only if it's already exists.

        Requires Redis 6.2.0 and higher.

        Specified by:
        addIfExistsAsync in interface RGeoAsync<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set
      • addIfExistsAsync

        public RFuture<Long> addIfExistsAsync​(GeoEntry... entries)
        Description copied from interface: RGeoAsync
        Adds geospatial members only if it's already exists.

        Requires Redis 6.2.0 and higher.

        Specified by:
        addIfExistsAsync in interface RGeoAsync<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set
      • tryAdd

        public boolean tryAdd​(double longitude,
                              double latitude,
                              V member)
        Description copied from interface: RGeo
        Adds geospatial member only if has not been added before.

        Requires Redis 6.2.0 and higher.

        Specified by:
        tryAdd in interface RGeo<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set
      • tryAdd

        public long tryAdd​(GeoEntry... entries)
        Description copied from interface: RGeo
        Adds geospatial members only if has not been added before.

        Requires Redis 6.2.0 and higher.

        Specified by:
        tryAdd in interface RGeo<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set
      • tryAddAsync

        public RFuture<Boolean> tryAddAsync​(double longitude,
                                            double latitude,
                                            V member)
        Description copied from interface: RGeoAsync
        Adds geospatial member only if has not been added before.

        Requires Redis 6.2.0 and higher.

        Specified by:
        tryAddAsync in interface RGeoAsync<V>
        Parameters:
        longitude - - longitude of object
        latitude - - latitude of object
        member - - object itself
        Returns:
        number of elements added to the sorted set
      • tryAddAsync

        public RFuture<Long> tryAddAsync​(GeoEntry... entries)
        Description copied from interface: RGeoAsync
        Adds geospatial members only if has not been added before.

        Requires Redis 6.2.0 and higher.

        Specified by:
        tryAddAsync in interface RGeoAsync<V>
        Parameters:
        entries - - objects
        Returns:
        number of elements added to the sorted set
      • dist

        public Double dist​(V firstMember,
                           V secondMember,
                           GeoUnit geoUnit)
        Description copied from interface: RGeo
        Returns distance between members in GeoUnit units.
        Specified by:
        dist in interface RGeo<V>
        Parameters:
        firstMember - - first object
        secondMember - - second object
        geoUnit - - geo unit
        Returns:
        distance
      • distAsync

        public RFuture<Double> distAsync​(V firstMember,
                                         V secondMember,
                                         GeoUnit geoUnit)
        Description copied from interface: RGeoAsync
        Returns distance between members in GeoUnit units.
        Specified by:
        distAsync in interface RGeoAsync<V>
        Parameters:
        firstMember - - first object
        secondMember - - second object
        geoUnit - - geo unit
        Returns:
        distance
      • hash

        public Map<V,​String> hash​(V... members)
        Description copied from interface: RGeo
        Returns 11 characters long Geohash string mapped by defined member.
        Specified by:
        hash in interface RGeo<V>
        Parameters:
        members - - objects
        Returns:
        hash mapped by object
      • hashAsync

        public RFuture<Map<V,​String>> hashAsync​(V... members)
        Description copied from interface: RGeoAsync
        Returns 11 characters Geohash string mapped by defined member.
        Specified by:
        hashAsync in interface RGeoAsync<V>
        Parameters:
        members - - objects
        Returns:
        hash mapped by object
      • pos

        public Map<V,​GeoPosition> pos​(V... members)
        Description copied from interface: RGeo
        Returns geo-position mapped by defined member.
        Specified by:
        pos in interface RGeo<V>
        Parameters:
        members - - objects
        Returns:
        geo position mapped by object
      • posAsync

        public RFuture<Map<V,​GeoPosition>> posAsync​(V... members)
        Description copied from interface: RGeoAsync
        Returns geo-position mapped by defined member.
        Specified by:
        posAsync in interface RGeoAsync<V>
        Parameters:
        members - - objects
        Returns:
        geo position mapped by object
      • search

        public List<V> search​(GeoSearchArgs args)
        Description copied from interface: RGeo
        Returns the members of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         List objects = geo.search(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         List objects = geo.search(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        search in interface RGeo<V>
        Parameters:
        args - - search conditions object
        Returns:
        list of memebers
      • searchAsync

        public RFuture<List<V>> searchAsync​(GeoSearchArgs args)
        Description copied from interface: RGeoAsync
        Returns the members of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         RFuture objects = geo.searchAsync(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         RFuture objects = geo.searchAsync(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        searchAsync in interface RGeoAsync<V>
        Parameters:
        args - - search conditions object
        Returns:
        list of memebers
      • searchWithDistance

        public Map<V,​Double> searchWithDistance​(GeoSearchArgs args)
        Description copied from interface: RGeo
        Returns the distance mapped by member of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         List objects = geo.searchWithDistance(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         List objects = geo.searchWithDistance(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        searchWithDistance in interface RGeo<V>
        Parameters:
        args - - search conditions object
        Returns:
        distance mapped by object
      • searchWithDistanceAsync

        public RFuture<Map<V,​Double>> searchWithDistanceAsync​(GeoSearchArgs args)
        Description copied from interface: RGeoAsync
        Returns the distance mapped by member of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         RFuture objects = geo.searchWithDistanceAsync(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         RFuture objects = geo.searchWithDistanceAsync(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        searchWithDistanceAsync in interface RGeoAsync<V>
        Parameters:
        args - - search conditions object
        Returns:
        distance mapped by object
      • searchWithPosition

        public Map<V,​GeoPosition> searchWithPosition​(GeoSearchArgs args)
        Description copied from interface: RGeo
        Returns the position mapped by member of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         List objects = geo.searchWithPosition(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         List objects = geo.searchWithPosition(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        searchWithPosition in interface RGeo<V>
        Parameters:
        args - - search conditions object
        Returns:
        position mapped by object
      • searchWithPositionAsync

        public RFuture<Map<V,​GeoPosition>> searchWithPositionAsync​(GeoSearchArgs args)
        Description copied from interface: RGeoAsync
        Returns the position mapped by member of a sorted set, which are within the borders of specified search conditions.

        Usage examples:

         List objects = geo.searchWithPosition(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         List objects = geo.searchWithPosition(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         

        Requires Redis 3.2.10 and higher.

        Specified by:
        searchWithPositionAsync in interface RGeoAsync<V>
        Parameters:
        args - - search conditions object
        Returns:
        position mapped by object
      • radius

        public List<V> radius​(double longitude,
                              double latitude,
                              double radius,
                              GeoUnit geoUnit)
        Specified by:
        radius in interface RGeo<V>
      • radius

        public List<V> radius​(double longitude,
                              double latitude,
                              double radius,
                              GeoUnit geoUnit,
                              int count)
        Specified by:
        radius in interface RGeo<V>
      • radius

        public List<V> radius​(double longitude,
                              double latitude,
                              double radius,
                              GeoUnit geoUnit,
                              GeoOrder geoOrder)
        Specified by:
        radius in interface RGeo<V>
      • radius

        public List<V> radius​(double longitude,
                              double latitude,
                              double radius,
                              GeoUnit geoUnit,
                              GeoOrder geoOrder,
                              int count)
        Specified by:
        radius in interface RGeo<V>
      • radiusWithDistance

        public Map<V,​Double> radiusWithDistance​(double longitude,
                                                      double latitude,
                                                      double radius,
                                                      GeoUnit geoUnit,
                                                      int count)
        Specified by:
        radiusWithDistance in interface RGeo<V>
      • radius

        public List<V> radius​(V member,
                              double radius,
                              GeoUnit geoUnit)
        Specified by:
        radius in interface RGeo<V>
      • radius

        public List<V> radius​(V member,
                              double radius,
                              GeoUnit geoUnit,
                              int count)
        Specified by:
        radius in interface RGeo<V>
      • radiusStoreTo

        public long radiusStoreTo​(String destName,
                                  double longitude,
                                  double latitude,
                                  double radius,
                                  GeoUnit geoUnit)
        Specified by:
        radiusStoreTo in interface RGeo<V>
      • storeSearchTo

        public long storeSearchTo​(String destName,
                                  GeoSearchArgs args)
        Description copied from interface: RGeo
        Finds the members of a sorted set, which are within the borders of specified search conditions.

        Stores result to destName.

        Usage examples:

         long count = geo.storeSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         long count = geo.storeSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         
        Specified by:
        storeSearchTo in interface RGeo<V>
        args - - search conditions object
        Returns:
        length of result
      • storeSearchToAsync

        public RFuture<Long> storeSearchToAsync​(String destName,
                                                GeoSearchArgs args)
        Description copied from interface: RGeoAsync
        Finds the members of a sorted set, which are within the borders of specified search conditions.

        Stores result to destName.

        Usage examples:

         long count = geo.storeSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         long count = geo.storeSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         
        Specified by:
        storeSearchToAsync in interface RGeoAsync<V>
        args - - search conditions object
        Returns:
        length of result
      • radiusStoreTo

        public long radiusStoreTo​(String destName,
                                  double longitude,
                                  double latitude,
                                  double radius,
                                  GeoUnit geoUnit,
                                  int count)
        Specified by:
        radiusStoreTo in interface RGeo<V>
      • radiusStoreTo

        public long radiusStoreTo​(String destName,
                                  double longitude,
                                  double latitude,
                                  double radius,
                                  GeoUnit geoUnit,
                                  GeoOrder geoOrder,
                                  int count)
        Specified by:
        radiusStoreTo in interface RGeo<V>
      • radiusStoreTo

        public long radiusStoreTo​(String destName,
                                  V member,
                                  double radius,
                                  GeoUnit geoUnit)
        Specified by:
        radiusStoreTo in interface RGeo<V>
      • radiusStoreTo

        public long radiusStoreTo​(String destName,
                                  V member,
                                  double radius,
                                  GeoUnit geoUnit,
                                  int count)
        Specified by:
        radiusStoreTo in interface RGeo<V>
      • storeSortedSearchTo

        public long storeSortedSearchTo​(String destName,
                                        GeoSearchArgs args)
        Description copied from interface: RGeo
        Finds the members of a sorted set, which are within the borders of specified search conditions.

        Stores result to destName sorted by distance.

        Usage examples:

         long count = geo.storeSortedSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         long count = geo.storeSortedSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         
        Specified by:
        storeSortedSearchTo in interface RGeo<V>
        args - - search conditions object
        Returns:
        length of result
      • storeSortedSearchToAsync

        public RFuture<Long> storeSortedSearchToAsync​(String destName,
                                                      GeoSearchArgs args)
        Description copied from interface: RGeoAsync
        Finds the members of a sorted set, which are within the borders of specified search conditions.

        Stores result to destName sorted by distance.

        Usage examples:

         long count = geo.storeSortedSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)
                                         .order(GeoOrder.ASC)
                                         .count(1)));
         
         long count = geo.storeSortedSearchTo(GeoSearchArgs.from(15, 37)
                                         .radius(200, GeoUnit.KILOMETERS)));
         
        Specified by:
        storeSortedSearchToAsync in interface RGeoAsync<V>
        args - - search conditions object
        Returns:
        length of result
      • radiusStoreSortedTo

        public long radiusStoreSortedTo​(String destName,
                                        double longitude,
                                        double latitude,
                                        double radius,
                                        GeoUnit geoUnit)
        Specified by:
        radiusStoreSortedTo in interface RGeo<V>
      • radiusStoreSortedTo

        public long radiusStoreSortedTo​(String destName,
                                        double longitude,
                                        double latitude,
                                        double radius,
                                        GeoUnit geoUnit,
                                        int count)
        Specified by:
        radiusStoreSortedTo in interface RGeo<V>
      • radiusStoreSortedTo

        public long radiusStoreSortedTo​(String destName,
                                        double longitude,
                                        double latitude,
                                        double radius,
                                        GeoUnit geoUnit,
                                        GeoOrder geoOrder,
                                        int count)
        Specified by:
        radiusStoreSortedTo in interface RGeo<V>
      • radiusStoreSortedTo

        public long radiusStoreSortedTo​(String destName,
                                        V member,
                                        double radius,
                                        GeoUnit geoUnit,
                                        int count)
        Specified by:
        radiusStoreSortedTo in interface RGeo<V>
      • expire

        public boolean expire​(long timeToLive,
                              TimeUnit timeUnit)
        Description copied from interface: RExpirable
        Specified by:
        expire in interface RExpirable
        Parameters:
        timeToLive - - timeout before object will be deleted
        timeUnit - - timeout time unit
        Returns:
        true if the timeout was set and false if not
      • expireAt

        public boolean expireAt​(long timestamp)
        Description copied from interface: RExpirable
        Specified by:
        expireAt in interface RExpirable
        Parameters:
        timestamp - - expire date in milliseconds (Unix timestamp)
        Returns:
        true if the timeout was set and false if not
      • expire

        public boolean expire​(Instant instant)
        Description copied from interface: RExpirable
        Sets an expiration date for this object. When expire date comes the key will automatically be deleted.
        Specified by:
        expire in interface RExpirable
        Parameters:
        instant - expire date
        Returns:
        true if the timeout was set and false if not
      • expireIfSet

        public boolean expireIfSet​(Instant time)
        Description copied from interface: RExpirable
        Sets an expiration date for this object only if it has been already set. When expire date comes the object will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfSet in interface RExpirable
        Parameters:
        time - expire date
        Returns:
        true if the timeout was set and false if not
      • expireIfNotSet

        public boolean expireIfNotSet​(Instant time)
        Description copied from interface: RExpirable
        Sets an expiration date for this object only if it hasn't been set before. When expire date comes the object will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfNotSet in interface RExpirable
        Parameters:
        time - expire date
        Returns:
        true if the timeout was set and false if not
      • expireIfGreater

        public boolean expireIfGreater​(Instant time)
        Description copied from interface: RExpirable
        Sets an expiration date for this object only if it's greater than expiration date set before. When expire date comes the object will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfGreater in interface RExpirable
        Parameters:
        time - expire date
        Returns:
        true if the timeout was set and false if not
      • expireIfLess

        public boolean expireIfLess​(Instant time)
        Description copied from interface: RExpirable
        Sets an expiration date for this object only if it's less than expiration date set before. When expire date comes the object will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfLess in interface RExpirable
        Parameters:
        time - expire date
        Returns:
        true if the timeout was set and false if not
      • expireAsync

        public RFuture<Boolean> expireAsync​(Instant instant)
        Description copied from interface: RExpirableAsync
        Set an expire date for object. When expire date comes the key will automatically be deleted.
        Specified by:
        expireAsync in interface RExpirableAsync
        Parameters:
        instant - - expire date
        Returns:
        true if the timeout was set and false if not
      • expire

        public boolean expire​(Duration duration)
        Description copied from interface: RExpirable
        Sets a timeout for this object. After the timeout has expired, the key will automatically be deleted.
        Specified by:
        expire in interface RExpirable
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • expireAsync

        public RFuture<Boolean> expireAsync​(Duration duration)
        Description copied from interface: RExpirableAsync
        Set a timeout for object. After the timeout has expired, the key will automatically be deleted.
        Specified by:
        expireAsync in interface RExpirableAsync
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • expireIfSet

        public boolean expireIfSet​(Duration duration)
        Description copied from interface: RExpirable
        Sets a timeout for this object only if it has been already set. After the timeout has expired, the key will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfSet in interface RExpirable
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • expireIfNotSet

        public boolean expireIfNotSet​(Duration duration)
        Description copied from interface: RExpirable
        Sets a timeout for this object only if it hasn't been set before. After the timeout has expired, the key will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfNotSet in interface RExpirable
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • expireIfGreater

        public boolean expireIfGreater​(Duration duration)
        Description copied from interface: RExpirable
        Sets a timeout for this object only if it's greater than timeout set before. After the timeout has expired, the key will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfGreater in interface RExpirable
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • expireIfLess

        public boolean expireIfLess​(Duration duration)
        Description copied from interface: RExpirable
        Sets a timeout for this object only if it's less than timeout set before. After the timeout has expired, the key will automatically be deleted.

        Requires Redis 7.0.0 and higher.

        Specified by:
        expireIfLess in interface RExpirable
        Parameters:
        duration - timeout before object will be deleted
        Returns:
        true if the timeout was set and false if not
      • clearExpire

        public boolean clearExpire()
        Description copied from interface: RExpirable
        Clear an expire timeout or expire date for object.
        Specified by:
        clearExpire in interface RExpirable
        Returns:
        true if timeout was removed false if object does not exist or does not have an associated timeout
      • clearExpireAsync

        public RFuture<Boolean> clearExpireAsync()
        Description copied from interface: RExpirableAsync
        Clear an expire timeout or expire date for object in async mode. Object will not be deleted.
        Specified by:
        clearExpireAsync in interface RExpirableAsync
        Returns:
        true if the timeout was cleared and false if not
      • remainTimeToLive

        public long remainTimeToLive()
        Description copied from interface: RExpirable
        Remaining time to live of Redisson object that has a timeout
        Specified by:
        remainTimeToLive in interface RExpirable
        Returns:
        time in milliseconds -2 if the key does not exist. -1 if the key exists but has no associated expire.
      • remainTimeToLiveAsync

        public RFuture<Long> remainTimeToLiveAsync()
        Description copied from interface: RExpirableAsync
        Remaining time to live of Redisson object that has a timeout
        Specified by:
        remainTimeToLiveAsync in interface RExpirableAsync
        Returns:
        time in milliseconds -2 if the key does not exist. -1 if the key exists but has no associated expire.
      • getExpireTime

        public long getExpireTime()
        Description copied from interface: RExpirable
        Expiration time of Redisson object that has a timeout

        Requires Redis 7.0.0 and higher.

        Specified by:
        getExpireTime in interface RExpirable
        Returns:
        expiration time