Package com.tangosol.net.cache

Class ReadWriteBackingMap

  • All Implemented Interfaces:
    CacheMap, ObservableMap, Map
    Direct Known Subclasses:
    ReadWriteSplittingBackingMap, VersionedBackingMap
    public class ReadWriteBackingMap
extends AbstractMap
implements CacheMap
    Backing Map implementation that provides a size-limited cache of a persistent store and supports configurable write-behind and refresh- ahead caching. This implementation is not intended to support null keys or null values.
    Author:
    cp 2002.11.25, jh 2005.02.08

    • Field Detail

      • BIN_STORE_PENDING

        protected static final Binary BIN_STORE_PENDING
        The binary form of the decoration indicating that the CacheStore on the primary member has not yet written the value.

      • GUARD_RECOVERY

        protected static final float GUARD_RECOVERY
        The recovery threshold to use for guarded execution of write-behind/refresh-ahead threads.
        See Also:
        Constant Field Values

      • MIN_REQUEUE_DELAY

        public static final long MIN_REQUEUE_DELAY
        The minimum "retry after requeue" time interval. Default value is 60 sec and can be overridden by the system property: 
         coherence.rwbm.requeue.delay

      • m_listenerSupport

        protected MapListenerSupport m_listenerSupport
        MapListenerSupport object.

    • Constructor Detail

      • ReadWriteBackingMap

        public ReadWriteBackingMap​(BackingMapManagerContext ctxService,
                           ObservableMap mapInternal,
                           Map mapMisses,
                           CacheLoader loader)
        Construct a ReadWriteBackingMap based on a CacheLoader (CacheStore).
        Parameters:
        ctxService - the context provided by the CacheService which is using this backing map
        mapInternal - the ObservableMap used to store the data internally in this backing map
        mapMisses - the Map used to cache CacheLoader misses (optional)
        loader - the CacheLoader responsible for the persistence of the cached data (optional)

      • ReadWriteBackingMap

        public ReadWriteBackingMap​(BackingMapManagerContext ctxService,
                           ObservableMap mapInternal,
                           Map mapMisses,
                           CacheLoader loader,
                           boolean fReadOnly,
                           int cWriteBehindSeconds,
                           double dflRefreshAheadFactor)
        Construct a ReadWriteBackingMap based on a CacheLoader (CacheStore).
        Parameters:
        ctxService - the context provided by the CacheService which is using this backing map
        mapInternal - the ObservableMap used to store the data internally in this backing map
        mapMisses - the Map used to cache CacheStore misses (optional)
        loader - the CacheLoader responsible for the persistence of the cached data (optional)
        fReadOnly - pass true is the specified loader is in fact a CacheStore that needs to be used only for read operations; changes to the cache will not be persisted
        cWriteBehindSeconds - number of seconds to write if there is a CacheStore; zero disables write-behind caching, which (combined with !fReadOnly) implies write-through
        dflRefreshAheadFactor - the interval before an entry expiration time (expressed as a percentage of the internal cache expiration interval) during which an asynchronous load request for the entry will be scheduled; zero disables refresh-ahead; only applicable when the mapInternal parameter is an instance of ConfigurableCacheMap

      • ReadWriteBackingMap

        public ReadWriteBackingMap​(BackingMapManagerContext ctxService,
                           ObservableMap mapInternal,
                           Map mapMisses,
                           BinaryEntryStore storeBinary,
                           boolean fReadOnly,
                           int cWriteBehindSeconds,
                           double dflRefreshAheadFactor)
        Construct a ReadWriteBackingMap based on a BinaryEntryStore.
        Parameters:
        ctxService - the context provided by the CacheService which is using this backing map
        mapInternal - the ObservableMap used to store the data internally in this backing map
        mapMisses - the Map used to cache CacheStore misses (optional)
        storeBinary - the BinaryEntryStore responsible for the persistence of the cached data (optional)
        fReadOnly - pass true is the specified loader is in fact a CacheStore that needs to be used only for read operations; changes to the cache will not be persisted
        cWriteBehindSeconds - number of seconds to write if there is a CacheStore; zero disables write-behind caching, which (combined with !fReadOnly) implies write-through
        dflRefreshAheadFactor - the interval before an entry expiration time (expressed as a percentage of the internal cache expiration interval) during which an asynchronous load request for the entry will be scheduled; zero disables refresh-ahead; only applicable when the mapInternal parameter is an instance of ConfigurableCacheMap
        Since:
        Coherence 3.6

      • ReadWriteBackingMap

        public ReadWriteBackingMap​(BackingMapManagerContext ctxService,
                           ObservableMap mapInternal,
                           Map mapMisses,
                           NonBlockingEntryStore storeBinary,
                           boolean fReadOnly,
                           int cWriteBehindSeconds,
                           double dflRefreshAheadFactor)
        Construct a ReadWriteBackingMap based on a NonBlockingEntryStore.
        Parameters:
        ctxService - the context provided by the CacheService which is using this backing map
        mapInternal - the ObservableMap used to store the data internally in this backing map
        mapMisses - the Map used to cache CacheStore misses (optional)
        storeBinary - the NonBlockingEntryStore responsible for the persistence of the cached data (optional)
        fReadOnly - pass true is the specified loader is in fact a CacheStore that needs to be used only for read operations; changes to the cache will not be persisted
        cWriteBehindSeconds - number of seconds to write if there is a CacheStore; zero disables write-behind caching, which (combined with !fReadOnly) implies write-through
        dflRefreshAheadFactor - the interval before an entry expiration time (expressed as a percentage of the internal cache expiration interval) during which an asynchronous load request for the entry will be scheduled; zero disables refresh-ahead; only applicable when the mapInternal parameter is an instance of ConfigurableCacheMap
        Since:
        Coherence 21.06

    • Method Detail

      • getContext

        public BackingMapManagerContext getContext()
        Get the context information provided by the CacheService.
        Returns:
        the CacheService's BackingMapManagerContext object that it provided to the BackingMapManager that created this backing map

      • getCacheService

        public CacheService getCacheService()
        Return the CacheService.
        Returns:
        the CacheService

      • isRethrowExceptions

        public boolean isRethrowExceptions()
        Determine if exceptions caught during synchronous CacheStore operations are rethrown to the calling thread; if false, exceptions are logged.
        Returns:
        true if CacheStore exceptions are rethrown to the calling thread

      • setRethrowExceptions

        public void setRethrowExceptions​(boolean fRethrow)
        Set the value of the flag that determines if exceptions caught during synchronous CacheStore operations are rethrown to the calling thread; if false, exceptions are logged.
        Parameters:
        fRethrow - true to indicate that exceptions should be rethrown

      • getRefreshAheadFactor

        public double getRefreshAheadFactor()
        Return the refresh-ahead factor.

        The refresh-ahead factor is used to calculate the "soft-expiration" time for cache entries. Soft-expiration is the point in time prior to the actual expiration after which any access request for an entry will schedule an asynchronous load request for the entry.

        The value of this property is expressed as a percentage of the internal cache expiration interval. If zero, refresh-ahead scheduling is disabled.

        Returns:
        the refresh-ahead factor

      • setRefreshAheadFactor

        public void setRefreshAheadFactor​(double dflRefreshAheadFactor)
        Set the refresh-ahead factor, expressed as a percentage of the internal cache expiration interval. Valid values are doubles in the interval [0.0, 1.0].

        This method has no effect if refresh-ahead is disabled.

        Parameters:
        dflRefreshAheadFactor - the new refresh-ahead factor
        See Also:
        getRefreshAheadFactor()

      • isReadOnly

        public boolean isReadOnly()
        Determine if the backing map should send data changes through the CacheStore, or should just keep them in memory.
        Returns:
        false to send changes to CacheStore (a read-write cache), or true to just keep them in memory (a read-only cache)

      • isRefreshAhead

        public boolean isRefreshAhead()
        Determine if the backing map preemptively reads soon-to-be expired entries on a refresh-ahead thread.
        Returns:
        true if refresh-ahead is enabled

      • getWriteMaxBatchSize

        public int getWriteMaxBatchSize()
        Get the maximum size of the write-behind batch.
        Returns:
        the maximum number of entries in the write-behind batch

      • setWriteMaxBatchSize

        public void setWriteMaxBatchSize​(int cWriteMaxBatchSize)
        Set the maximum size of a batch. The size is used to reduce the size of the write-behind batches and the amount of [scratch] memory used to keep de-serialized entries passed to the storeAll operations.

        This method has no effect if write-behind is disabled.

        Parameters:
        cWriteMaxBatchSize - the maximum batch size

      • getWriteBatchFactor

        public double getWriteBatchFactor()
        Return the write-batch factor.

        The write-batch factor is used to calculate the "soft-ripe" time for write-behind queue entries. A queue entry is considered to be "ripe" for a write operation if it has been in the write-behind queue for no less than the write-behind interval. The "soft-ripe" time is the point in time prior to the actual ripe time after which an entry will be included in a batched asynchronous write operation to the CacheStore (along with all other ripe and soft-ripe entries). In other words, a soft-ripe entry is an entry that has been in the write-behind queue for at least the following duration: 

         D' = (1.0 - F)*D
        where: 
         D = write-behind delay
 F = write-batch factor
        Conceptually, the write-behind thread uses the following logic when performing a batched update:
        1. The thread waits for a queued entry to become ripe.
        2. When an entry becomes ripe, the thread dequeues all ripe and soft-ripe entries in the queue.
        3. The thread then writes all ripe and soft-ripe entries either via store() (if there is only the single ripe entry) or storeAll() (if there are multiple ripe/soft-ripe entries).
        4. The thread then repeats (1).

        This property is only applicable if asynchronous writes are enabled and the CacheStore implements the storeAll() method.

        The value of this property is expressed as a percentage of the write-behind interval. Valid values are doubles in the interval [0.0, 1.0].

        Returns:
        the write-batch factor

      • setWriteBatchFactor

        public void setWriteBatchFactor​(double dflWriteBatchFactor)
        Set the write-batch factor, expressed as a percentage of the write-behind interval. Valid values are doubles in the interval [0.0, 1.0].

        This method has no effect if write-behind is disabled.

        Parameters:
        dflWriteBatchFactor - the new write-batch factor
        See Also:
        getWriteBatchFactor()

      • isWriteBehind

        public boolean isWriteBehind()
        Determine if the backing map writes changes on a write-behind thread through the CacheStore.
        Returns:
        true implies changes are queued to be written asynchronously

      • getWriteBehindSeconds

        public int getWriteBehindSeconds()
        Return the number of seconds between write-behind writes to the CacheStore or 0 if write-behind is not enabled.
        Returns:
        the number of seconds between write-behind writes

      • setWriteBehindSeconds

        public void setWriteBehindSeconds​(int cSecs)
        Set the number of seconds between write-behind writes to the CacheStore.

        This method has not effect if write-behind is not enabled.

        Parameters:
        cSecs - the new write-behind delay in seconds

      • getWriteBehindMillis

        public long getWriteBehindMillis()
        Return the number of milliseconds between write-behind writes to the CacheStore or 0 if write-behind is not enabled.
        Returns:
        the number of milliseconds between write-behind writes
        Since:
        Coherence 3.4

      • setWriteBehindMillis

        public void setWriteBehindMillis​(long cMillis)
        Set the number of milliseconds between write-behind writes to the CacheStore.

        This method has not effect if write-behind is not enabled.

        Parameters:
        cMillis - the new write-behind delay in milliseconds
        Since:
        Coherence 3.4

      • getWriteRequeueThreshold

        public int getWriteRequeueThreshold()
        Return the maximum size of the write-behind queue for which failed CacheStore write operations are requeued or 0 if write-behind requeueing is disabled.
        Returns:
        the write-behind requeue threshold

      • setWriteRequeueThreshold

        public void setWriteRequeueThreshold​(int cThreshold)
        Set the maximum size of the write-behind queue for which failed CacheStore write operations are requeued.

        This method has not effect if write-behind is not enabled.

        Parameters:
        cThreshold - the new write-behind requeue threshold

      • isWriteThrough

        public boolean isWriteThrough()
        Determine if the backing map writes changes immediately through the CacheStore.
        Returns:
        true implies that changes to the backing map are written synchronously to the CacheStore

      • getCacheStoreTimeoutMillis

        public long getCacheStoreTimeoutMillis()
        Return the timeout used for CacheStore operations, or 0 if no timeout is specified.
        Returns:
        the CacheStore timeout

      • setCacheStoreTimeoutMillis

        public void setCacheStoreTimeoutMillis​(long cStoreTimeoutMillis)
        Set the timeout used for CacheStore operations. A value of 0 indicates to use the default guardian timeout of the associated service.
        Parameters:
        cStoreTimeoutMillis - the CacheStore timeout, or 0 for the default guardian timeout

      • setCacheName

        public void setCacheName​(String sCacheName)
        Set the cache name for ReadThread and WriteThread if not already set.
        Parameters:
        sCacheName - the name of the cache

      • getPendingWrites

        public int getPendingWrites()
        Return the size of the write-behind queue if configured, or the number of pending writes of the non-blocking store, if configured. Return -1 if neither.
        Returns:
        number of pending writes

      • clear

        public void clear()
        Remove everything from the Map.
        Specified by:
        clear in interface Map
        Overrides:
        clear in class AbstractMap

      • containsKey

        public boolean containsKey​(Object oKey)
        Returns true if this map contains a mapping for the specified key.
        Specified by:
        containsKey in interface Map
        Overrides:
        containsKey in class AbstractMap
        Parameters:
        oKey - the key to test for
        Returns:
        true if this map contains a mapping for the specified key, false otherwise.

      • containsValue

        public boolean containsValue​(Object oValue)
        Returns true if this CachingMap maps one or more keys to the specified value.
        Specified by:
        containsValue in interface Map
        Overrides:
        containsValue in class AbstractMap
        Parameters:
        oValue - the value to test for
        Returns:
        true if this CachingMap maps one or more keys to the specified value, false otherwise

      • get

        public Object get​(Object oKey)
        Returns the value to which this map maps the specified key.
        Specified by:
        get in interface Map
        Overrides:
        get in class AbstractMap
        Parameters:
        oKey - the key object
        Returns:
        the value to which this map maps the specified key, or null if the map contains no mapping for this key

      • put

        public Object put​(Object oKey,
                  Object oValue)
        Associates the specified value with the specified key in this map.
        Specified by:
        put in interface CacheMap
        Specified by:
        put in interface Map
        Overrides:
        put in class AbstractMap
        Parameters:
        oKey - key with which the specified value is to be associated
        oValue - value to be associated with the specified key
        Returns:
        previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key, if the implementation supports null values.

      • remove

        public Object remove​(Object oKey)
        Removes the mapping for this key from this map if present. Expensive: updates both the underlying cache and the local cache.
        Specified by:
        remove in interface Map
        Overrides:
        remove in class AbstractMap
        Parameters:
        oKey - key whose mapping is to be removed from the map
        Returns:
        previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key, if the implementation supports null values.

      • putAll

        public void putAll​(Map map)
        Associates the specified values with the respective keys in this map. Be aware that the keys will be locked in the order they are returned from iterating over the map passed in and unlocked at the end of the method. This method is called internally within Coherence and the keys will have been locked at the Service level already, so concurrent calls to this method with the same keys will not be an issue. If this method is somehow called directly by application code, which is not recommended, then it is advisable to pass in a sorted map that sorts the keys by their natural ordering.
        Specified by:
        putAll in interface Map
        Overrides:
        putAll in class AbstractMap
        Parameters:
        map - keys and values which are to be associated in this map

      • putToInternalMap

        protected Object putToInternalMap​(Object binKey,
                                  Object binValue,
                                  long cExpiry)
        Put the specified key in internal format and value in internal format into the internal backing map. If the cExpiry parameter is greater than the default expiry value CacheMap.EXPIRY_DEFAULT and the internal map is not an instance of CacheMap then an exception will be thrown.
        Parameters:
        binKey - the key in internal format
        binValue - the value in internal format; null if the value should be cached as "missing"
        cExpiry - the cache entry expiry value
        Returns:
        any previous value tht was mapped to the key.
        Throws:
        UnsupportedOperationException - if the value of cExpiry is greater than CacheMap.EXPIRY_DEFAULT and the internal map is not an instance of CacheMap.

      • removeInternal

        protected Object removeInternal​(Object oKey,
                                boolean fBlind)
        Implementation of the remove() API.
        Parameters:
        oKey - key whose mapping is to be removed from the map
        fBlind - if true, the return value will be ignored
        Returns:
        previous value associated with specified key, or null

      • size

        public int size()
        Returns the number of key-value mappings in this map. If the map contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.
        Specified by:
        size in interface Map
        Overrides:
        size in class AbstractMap
        Returns:
        the number of key-value mappings in this map

      • entrySet

        public Set entrySet()
        Returns an set view of the mappings contained in this map.
        Specified by:
        entrySet in interface Map
        Specified by:
        entrySet in class AbstractMap
        Returns:
        a set view of the mappings contained in this map

      • keySet

        public Set keySet()
        Returns an set view of the keys contained in this map.
        Specified by:
        keySet in interface Map
        Overrides:
        keySet in class AbstractMap
        Returns:
        a set view of the keys contained in this map

      • values

        public Collection values()
        Returns a collection view of the values contained in this map.
        Specified by:
        values in interface Map
        Overrides:
        values in class AbstractMap
        Returns:
        a collection view of the values contained in this map

      • put

        public Object put​(Object oKey,
                  Object oValue,
                  long cMillis)
        Associates the specified value with the specified key in this map.
        Specified by:
        put in interface CacheMap
        Parameters:
        oKey - key with which the specified value is to be associated
        oValue - value to be associated with the specified key
        cMillis - the number of milliseconds until the entry will expire; pass zero to use the cache's default ExpiryDelay settings; pass -1 to indicate that the entry should never expire
        Returns:
        previous value associated with specified key, or null if there was no mapping for key

      • getAll

        public Map getAll​(Collection colKeys)
        Retrieve values for all the specified keys.
        Specified by:
        getAll in interface CacheMap
        Parameters:
        colKeys - a collection of keys that may be in the named cache
        Returns:
        a Map of keys to values for the specified keys passed in colKeys

      • removeAll

        protected boolean removeAll​(Collection colKeys)
        Remove the collection of keys from this ReadWriteBackingMap.

        This method will ensure the configured CacheStore.eraseAll method is called with all owned keys in addition to removing the relevant entries from the internal Map.

        Parameters:
        colKeys - a collection of keys to remove, that may be in the map
        Returns:
        true if any of the provided keys were successfully removed from this map

      • putToInternalCache

        protected void putToInternalCache​(Object oKey,
                                  Object oVal)
        Add the key and value pair to the internal cache in such a way that the resulting map event would be marked as "synthetic".
        Parameters:
        oKey - the key in internal format
        oVal - the value in internal format; null if the value should be cached as "missing"

      • putToInternalCache

        protected void putToInternalCache​(ReadWriteBackingMap.Entry entry)
        Add the key and value pair to the internal cache in such a way that the resulting map event would be marked as "synthetic".
        Parameters:
        entry - cache entry

      • putToInternalCache

        protected void putToInternalCache​(Object oKey,
                                  Object oVal,
                                  long cMillis)
        Add the key and value pair to the internal cache in such a way that the resulting map event would be marked as "synthetic".
        Parameters:
        oKey - the key in internal format
        oVal - the value in internal format; null if the value should be cached as "missing"
        cMillis - the cache entry expiry value

      • cancelOutstandingReads

        protected void cancelOutstandingReads​(Object oKey)
        Cancel any outstanding asynchronous reads for a key.
        Parameters:
        oKey - the key in internal format

      • getFromInternalCache

        protected Object getFromInternalCache​(Object oKey)
        Get the the value for a given key. If the entry is present in the internal cache and refresh-ahead is configured, check if a reload operation needs to be scheduled. If the entry is missing, check for a potentially pending refresh-ahead operation and potentially pending write-behind.
        Parameters:
        oKey - the key in internal format
        Returns:
        the value or null if the value is not found

      • getCachedOrPending

        protected Object getCachedOrPending​(Object oKey)
        Get a value from the internal cache in a way that respects a potentially pending write-behind operation.
        Parameters:
        oKey - the key
        Returns:
        the corresponding value

      • putInternal

        protected Object putInternal​(Object oKey,
                             Object oValue,
                             long cMillis)
        An actual implementation for the extended put() method.
        Parameters:
        oKey - key with which the specified value is to be associated
        oValue - value to be associated with the specified key
        cMillis - the number of milliseconds until the entry will expire
        Returns:
        previous value associated with specified key, or null if there was no mapping for key.

      • waitFor

        protected boolean waitFor​(Object o,
                          long cMillis)
        Wait for notification on the specified object for no longer than the specified wait time.

        Note: the caller must hold synchronization on the object being waited on.

        Parameters:
        o - the object to wait for notification on
        cMillis - the maximum time in milliseconds to wait; pass 0 for forever
        Returns:
        true iff notification was received, the timeout has passed, or the thread was spuriously wakened; false if this thread was interrupted

      • heartbeat

        protected void heartbeat()
        Issue a service guardian "heartbeat" for the current thread.

      • extractExpiry

        protected long extractExpiry​(ReadWriteBackingMap.Entry entry)
        Return the expiration value for the given entry.
        Parameters:
        entry - the entry
        Returns:
        the expiration value

      • updateThreadName

        protected void updateThreadName​(Daemon daemon,
                                String sName)
        Append the provided name to the Daemon's thread name if not already appended.
        Parameters:
        daemon - the Daemon to be modified
        sName - the name to append to the Daemon's thread name

      • instantiateEntrySet

        protected ReadWriteBackingMap.EntrySet instantiateEntrySet()
        Factory pattern: instantiate an entry set for this backing map.
        Returns:
        a new EntrySet object

      • instantiateKeySet

        protected ReadWriteBackingMap.KeySet instantiateKeySet()
        Factory pattern: instantiate a key set for this backing map.
        Returns:
        a new KeySet object

      • instantiateValuesCollection

        protected ReadWriteBackingMap.ValuesCollection instantiateValuesCollection()
        Factory pattern.
        Returns:
        a new instance of the ValuesCollection class (or subclass thereof)

      • addMapListener

        public void addMapListener​(MapListener listener)
        Add a standard map listener that will receive all events (inserts, updates, deletes) that occur against the map, with the key, old-value and new-value included. This has the same result as the following call: 
           addMapListener(listener, (Filter) null, false);
        Specified by:
        addMapListener in interface ObservableMap
        Parameters:
        listener - the MapEvent listener to add

      • removeMapListener

        public void removeMapListener​(MapListener listener)
        Remove a standard map listener that previously signed up for all events. This has the same result as the following call: 
           removeMapListener(listener, (Filter) null);
        Specified by:
        removeMapListener in interface ObservableMap
        Parameters:
        listener - the listener to remove

      • addMapListener

        public void addMapListener​(MapListener listener,
                           Object oKey,
                           boolean fLite)
        Add a map listener for a specific key.

        The listeners will receive MapEvent objects, but if fLite is passed as true, they might not contain the OldValue and NewValue properties.

        To unregister the MapListener, use the ObservableMap.removeMapListener(MapListener, Object) method.

        Specified by:
        addMapListener in interface ObservableMap
        Parameters:
        listener - the MapEvent listener to add
        oKey - the key that identifies the entry for which to raise events
        fLite - true to indicate that the MapEvent objects do not have to include the OldValue and NewValue property values in order to allow optimizations

      • removeMapListener

        public void removeMapListener​(MapListener listener,
                              Object oKey)
        Remove a map listener that previously signed up for events about a specific key.
        Specified by:
        removeMapListener in interface ObservableMap
        Parameters:
        listener - the listener to remove
        oKey - the key that identifies the entry for which to raise events

      • addMapListener

        public void addMapListener​(MapListener listener,
                           Filter filter,
                           boolean fLite)
        Add a map listener that receives events based on a filter evaluation.

        The listeners will receive MapEvent objects, but if fLite is passed as true, they might not contain the OldValue and NewValue properties.

        To unregister the MapListener, use the ObservableMap.removeMapListener(MapListener, Filter) method.

        Specified by:
        addMapListener in interface ObservableMap
        Parameters:
        listener - the MapEvent listener to add
        filter - a filter that will be passed MapEvent objects to select from; a MapEvent will be delivered to the listener only if the filter evaluates to true for that MapEvent (see MapEventFilter); null is equivalent to a filter that alway returns true
        fLite - true to indicate that the MapEvent objects do not have to include the OldValue and NewValue property values in order to allow optimizations

      • removeMapListener

        public void removeMapListener​(MapListener listener,
                              Filter filter)
        Remove a map listener that previously signed up for events based on a filter evaluation.
        Specified by:
        removeMapListener in interface ObservableMap
        Parameters:
        listener - the listener to remove
        filter - the filter that was passed into the corresponding addMapListener() call

      • equals

        public boolean equals​(Object o)
        Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings.
        Specified by:
        equals in interface Map
        Overrides:
        equals in class AbstractMap
        Parameters:
        o - object to be compared for equality with this map
        Returns:
        true if the specified object is equal to this map

      • hashCode

        public int hashCode()
        Returns the hash code value for this map.
        Specified by:
        hashCode in interface Map
        Overrides:
        hashCode in class AbstractMap
        Returns:
        the hash code value for this map

      • toString

        public String toString()
        For debugging purposes, format the contents of the Map in a human- readable format.
        Overrides:
        toString in class AbstractMap
        Returns:
        a String representation of this ReadWriteBackingMap

      • getInternalCache

        public ObservableMap getInternalCache()
        Get the representative of the "in-memory" storage for this backing map.
        Returns:
        the ObservableMap object (never null) that this backing map uses to store entries

      • getInternalConfigurableCache

        protected ConfigurableCacheMap getInternalConfigurableCache()
        Get the map that provides internal storage for this backing map. If the internal storage is a ConfigurableCacheMap, then this accessor returns the same reference as getInternalCache(); otherwise it returns null. The refresh-ahead implementation relies on the internal storage providing the ConfigurableCacheMap interface, so this method will always return a non-null value if refresh-ahead is enabled.
        Returns:
        the cache for this backing map or null if the internal map is not an implementation of the ConfigurableCacheMap interface

      • configureInternalCache

        protected void configureInternalCache​(ObservableMap mapInternal)
        Configure the internal cache that this backing map uses to store its "in-memory" data.
        Parameters:
        mapInternal - the internal map

      • getMissesCache

        public Map getMissesCache()
        Get the optional map used to cache CacheLoader (or CacheStore) misses.
        Returns:
        the Map that this backing map uses to cache CacheLoader (or CacheStore) misses or null if misses are not cached

      • getControlMap

        public ConcurrentMap getControlMap()
        Get the concurrency control map for this backing map.
        Returns:
        the ObservableMap object (never null) that this backing map uses to store entries

      • instantiateControlMap

        protected ConcurrentMap instantiateControlMap()
        Factory pattern: Create the concurrency control map for this backing map.
        Returns:
        a new concurrency control map

      • getSyntheticEventsMap

        protected Map getSyntheticEventsMap()
        Get the map of keys for which the events should be marked as synthetic (internal).
        Returns:
        the map of keys to mark events as internal

      • getInternalListener

        protected MapListener getInternalListener()
        Obtain the MapListener that listens to the internal cache and routes those events to anyone listening to this ReadWriteBackingMap, creating such a listener if one does not already exist.
        Returns:
        a routing MapListener

      • instantiateInternalListener

        protected MapListener instantiateInternalListener()
        Factory pattern: Create a MapListener that listens to the internal cache and routes those events to anyone listening to this ReadWriteBackingMap.
        Returns:
        a new routing MapListener

      • release

        public void release()
        Release the backing map when it is no longer being used.

      • isActive

        public boolean isActive()
        Determine if the backing map is still active.
        Returns:
        true if the backing map is still active

      • instantiateReadLatch

        protected ReadWriteBackingMap.ReadLatch instantiateReadLatch​(Object oKey)
        Factory pattern: Instantiate a new read latch the given key.
        Parameters:
        oKey - the key
        Returns:
        the read latch

      • getReadQueue

        public ReadWriteBackingMap.ReadQueue getReadQueue()
        Get the queue of keys that are yet to be read.
        Returns:
        the refresh-ahead queue object

      • instantiateReadQueue

        protected ReadWriteBackingMap.ReadQueue instantiateReadQueue()
        Factory pattern: Instantiate a new ReadQueue object.
        Returns:
        a new ReadQueue object

      • getWriteQueue

        public ReadWriteBackingMap.WriteQueue getWriteQueue()
        Get the queue of entries that are yet to be written.
        Returns:
        the write-behind queue object

      • flush

        public void flush()
        Flush the write-behind queue, writing everything immediately.

      • removeFromWriteQueue

        protected ReadWriteBackingMap.Entry removeFromWriteQueue​(Object binKey)
        Remove the specified entry from the WriteQueue.
        Parameters:
        binKey - the key
        Returns:
        the currently queued entry (could be NO_VALUE marker or null)

      • instantiateEntry

        protected ReadWriteBackingMap.Entry instantiateEntry​(Object oKey,
                                                     Object oValue,
                                                     Object oValueOrig)
        Factory pattern: instantiate a queue entry.
        Parameters:
        oKey - the key for the new entry
        oValue - the entry's value; could be null representing a non-existing or removed entry
        oValueOrig - the entry's original value; could be null representing a non-existing entry
        Returns:
        a new Entry

      • instantiateEntry

        protected ReadWriteBackingMap.Entry instantiateEntry​(Object oKey,
                                                     Object oValue,
                                                     Object oValueOrig,
                                                     long cExpiry)
        Factory pattern: instantiate a queue entry.
        Parameters:
        oKey - the key for the new entry
        oValue - the entry's value; could be null representing a non-existing or removed entry
        oValueOrig - the entry's original value; could be null representing a non-existing entry
        cExpiry - the expiry delay, or CacheMap.EXPIRY_NEVER or CacheMap.EXPIRY_DEFAULT
        Returns:
        a new Entry

      • instantiateWriteQueue

        protected ReadWriteBackingMap.WriteQueue instantiateWriteQueue()
        Factory pattern: Instantiate a new WriteQueue object.
        Returns:
        a new WriteQueue object

      • getReadThread

        protected ReadWriteBackingMap.ReadThread getReadThread()
        Get the refresh-ahead thread.
        Returns:
        the refresh-ahead thread or null if refresh-ahead is not enabled

      • configureReadThread

        protected void configureReadThread​(double dflRefreshAheadFactor)
        Set up the optional refresh-ahead thread and queue that this backing map will use.

        This method has no effect if the given refresh-ahead factor is zero or the cache returned by getInternalConfigurableCache() is null or non-expiring.

        Parameters:
        dflRefreshAheadFactor - the refresh-ahead factor expressed as a percentage of the internal cache expiry

      • instantiateReadThread

        protected ReadWriteBackingMap.ReadThread instantiateReadThread()
        Factory pattern: Instantiate the refresh-ahead thread.
        Returns:
        a new refresh-ahead thread

      • terminateReadThread

        protected void terminateReadThread()
        Terminate the refresh-ahead thread.

      • getWriteThread

        protected ReadWriteBackingMap.WriteThread getWriteThread()
        Get the write-behind thread.
        Returns:
        the write-behind thread or null if there is no CacheStore to write to

      • configureWriteThread

        protected void configureWriteThread​(int cWriteBehindSeconds)
        Set up the optional write-behind thread and queue that this backing map will use.

        This method has no effect if the given write-behind delay is zero or isReadOnly() returns true.

        Parameters:
        cWriteBehindSeconds - write-behind delay

      • instantiateWriteThread

        protected ReadWriteBackingMap.WriteThread instantiateWriteThread()
        Factory pattern: Instantiate the write-behind thread.
        Returns:
        a new write-behind thread

      • terminateWriteThread

        protected void terminateWriteThread()
        Terminate the write-behind thread.

      • getCacheStore

        public ReadWriteBackingMap.StoreWrapper getCacheStore()
        Get the representative of the "persistent" storage for this backing map.
        Returns:
        the cache store wrapper object that this backing map uses for persistence or null if there is no persistent store behind this backing map

      • configureCacheStore

        protected void configureCacheStore​(ReadWriteBackingMap.StoreWrapper store,
                                   boolean fReadOnly)
        Set up the StoreWrapper that this backing map will use.
        Parameters:
        store - the StoreWrapper that this backing map will delegate persistence responsibilities to
        fReadOnly - pass true to prevent the usage of the cache store write operations

      • instantiateCacheStoreWrapper

        protected ReadWriteBackingMap.StoreWrapper instantiateCacheStoreWrapper​(CacheStore store)
        Factory pattern: Instantiate a StoreWrapper wrapper around the passed CacheStore. (Supports CacheStore extension by delegation pattern.)
        Parameters:
        store - the CacheStore to wrap
        Returns:
        the StoreWrapper wrapper that can supplement and override the operations of the supplied CacheStore

      • instantiateCacheStoreWrapper

        protected ReadWriteBackingMap.StoreWrapper instantiateCacheStoreWrapper​(BinaryEntryStore store)
        Factory pattern: Instantiate a StoreWrapper wrapper around the passed BinaryEntryStore. (Supports BinaryEntryStore extension by delegation pattern.)
        Parameters:
        store - the BinaryEntryStore to wrap
        Returns:
        the StoreWrapper wrapper that can supplement and override the operations of the supplied BinaryEntryStore

      • instantiateCacheStoreWrapper

        protected ReadWriteBackingMap.StoreWrapper instantiateCacheStoreWrapper​(NonBlockingEntryStore store)
        Factory pattern: Instantiate a StoreWrapper wrapper around the passed NonBlockingEntryStore. (Supports NonBlockingEntryStore extension by delegation pattern.)
        Parameters:
        store - the NonBlockingEntryStore to wrap
        Returns:
        the StoreWrapper wrapper that can supplement and override the operations of the supplied BinaryEntryStore

      • instantiateCacheLoaderCacheStore

        protected CacheStore instantiateCacheLoaderCacheStore​(CacheLoader loader)
        Factory pattern: Instantiate a CacheLoaderCacheStore wrapper around a passed CacheLoader.
        Parameters:
        loader - the CacheLoader to wrap; never null
        Returns:
        a CacheStore instance