com.hazelcast.map.impl

Class MapStoreWrapper

java.lang.Object

com.hazelcast.map.impl.MapStoreWrapper

All Implemented Interfaces:

MapLoader, MapLoaderLifecycleSupport, MapStore

public class MapStoreWrapper
extends Object
implements MapStore, MapLoaderLifecycleSupport

Constructor Summary

Constructors

Constructor and Description
MapStoreWrapper(String mapName, Object impl)

Method Summary

Modifier and Type	Method and Description
void	delete(Object key) Deletes the entry with a given key from the store.
void	deleteAll(Collection keys) Deletes multiple entries from the store.
void	destroy() Hazelcast will call this method before shutting down.
Object	getImpl()
MapStore	getMapStore()
void	init(HazelcastInstance hazelcastInstance, Properties properties, String mapName) Initializes this MapLoader implementation.
void	instrument(NodeEngine nodeEngine)
boolean	isMapLoader()
boolean	isPostProcessingMapStore()
Object	load(Object key) Loads the value of a given key.
Map	loadAll(Collection keys) Loads given keys.
Iterable<Object>	loadAllKeys() Returns an Iterable of all keys or null if a map loader is not configured for this map.
void	store(Object key, Object value) Stores the key-value pair.
void	storeAll(Map map) Stores multiple entries.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

MapStoreWrapper

public MapStoreWrapper(String mapName,
                       Object impl)

Method Detail

getMapStore

public MapStore getMapStore()

destroy

public void destroy()

Description copied from interface: MapLoaderLifecycleSupport

Hazelcast will call this method before shutting down. This method can be overridden to clean up the resources held by this map loader implementation, such as closing the database connections, etc.

Specified by:

destroy in interface MapLoaderLifecycleSupport

init

public void init(HazelcastInstance hazelcastInstance,
                 Properties properties,
                 String mapName)

Description copied from interface: MapLoaderLifecycleSupport

Initializes this MapLoader implementation. Hazelcast will call this method when the map is first used on the HazelcastInstance. Implementation can initialize required resources for the implementing mapLoader, such as reading a config file and/or creating a database connection. References to maps, other than the one on which this MapLoader is configured, can be obtained from the hazelcastInstance in this method's implementation.

On members joining a cluster, this method is executed during finalization of the join operation, therefore care should be taken to adhere to the rules for PostJoinAwareService.getPostJoinOperation(). If the implementation executes operations which may wait on locks or otherwise block (e.g. waiting for network operations), this may result in a time-out and obstruct the new member from joining the cluster. If blocking operations are required for initialization of the MapLoader, consider deferring them with a lazy initialization scheme.

Specified by:

init in interface MapLoaderLifecycleSupport

Parameters:

hazelcastInstance - HazelcastInstance of this mapLoader.

properties - Properties set for this mapStore. see MapStoreConfig

mapName - name of the map.

isMapLoader

public boolean isMapLoader()

Returns:

true if a MapLoader is configured for this map

instrument

public void instrument(NodeEngine nodeEngine)

delete

public void delete(Object key)

Description copied from interface: MapStore

Deletes the entry with a given key from the store.

If an exception is thrown the remove operation will fail.

Specified by:

delete in interface MapStore

Parameters:

key - the key to delete from the store

store

public void store(Object key,
                  Object value)

Description copied from interface: MapStore

Stores the key-value pair.

If an exception is thrown then the put operation will fail.

Specified by:

store in interface MapStore

Parameters:

key - key of the entry to store

value - value of the entry to store

storeAll

public void storeAll(Map map)

Description copied from interface: MapStore

Stores multiple entries.

Implementation of this method can optimize the store operation by storing all entries in one database connection. storeAll() is used when writeDelaySeconds is positive (write-behind).If an exception is thrown, the entries will try to be stored one by one using the store() method.

Note: on the retry phase only entries left in the map will be stored one-by-one. In this way a MapStore implementation can handle partial storeAll() cases when some entries were stored successfully before a failure happens. Entries removed from the map will be not passed to subsequent call to store() method any more.

Specified by:

storeAll in interface MapStore

Parameters:

map - map of entries to store

deleteAll

public void deleteAll(Collection keys)

Description copied from interface: MapStore

Deletes multiple entries from the store.

If an exception is thrown the entries will try to be deleted one by one using the delete() method.

Note: on the retry phase only entries left in the keys will be deleted one-by-one. In this way a MapStore implementation can handle partial deleteAll() cases when some entries were deleted successfully before a failure happens. Entries removed from the keys will be not passed to subsequent call to delete() method any more.

Specified by:

deleteAll in interface MapStore

Parameters:

keys - the keys of the entries to delete.

loadAllKeys

public Iterable<Object> loadAllKeys()

Returns an Iterable of all keys or null if a map loader is not configured for this map. Loads all of the keys from the store. The returned Iterable may return the keys lazily by loading them in batches. The Iterator of this Iterable may implement the Closeable interface in which case it will be closed once iteration is over. This is intended for releasing resources such as closing a JDBC result set.

The returned Iterable should not contain any null keys.

Specified by:

loadAllKeys in interface MapLoader

Returns:

all the keys. Keys inside the Iterable cannot be null.

load

public Object load(Object key)

Description copied from interface: MapLoader

Loads the value of a given key. If distributed map doesn't contain the value for the given key then Hazelcast will call implementation's load (key) method to obtain the value. Implementation can use any means of loading the given key; such as an O/R mapping tool, simple SQL or reading a file etc.

Specified by:

load in interface MapLoader

Returns:

value of the key; returning null value signals value missing in the underlying store

loadAll

public Map loadAll(Collection keys)

Description copied from interface: MapLoader

Loads given keys. This is batch load operation so that implementation can optimize the multiple loads.

For any key in the input keys, there should be a single mapping in the resulting map. Also the resulting map should not have any keys that are not part of the input keys.

The given collection should not contain any null keys. The returned Map should not contain any null keys or values.

Loading other items than what provided in keys prevents the map from being filled from the map store.

Specified by:

loadAll in interface MapLoader

Parameters:

keys - keys of the values entries to load

Returns:

map of loaded key-value pairs.

getImpl

public Object getImpl()

isPostProcessingMapStore

public boolean isPostProcessingMapStore()

toString

public String toString()

Overrides:

toString in class Object