Class NullLevel2Cache

java.lang.Object

org.datanucleus.cache.AbstractLevel2Cache

org.datanucleus.cache.NullLevel2Cache

All Implemented Interfaces:

Serializable, Level2Cache

public class NullLevel2Cache
extends AbstractLevel2Cache

Null implementation of a Level 2 Cache. Does nothing when its methods are invoked.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static final String	NAME
private static final long	serialVersionUID

Fields inherited from class AbstractLevel2Cache

cacheName, clearAtClose, expiryMillis, maxSize, nucleusCtx

Constructor Summary

Constructors

Constructor	Description
NullLevel2Cache(NucleusContext nucleusCtx)

Method Summary

Modifier and Type	Method	Description
void	close()	Method to close the cache when no longer needed.
boolean	containsOid(Object oid)	Accessor for whether an object with the specified id is in the cache
void	evict(Object oid)	Evict the parameter instance from the second-level cache.
void	evictAll()	Evict the parameter instances from the second-level cache.
void	evictAll(Class pcClass, boolean subclasses)	Evict the parameter instances from the second-level cache.
void	evictAll(Object[] oids)	Evict the parameter instances from the second-level cache.
void	evictAll(Collection oids)	Evict the parameter instances from the second-level cache.
CachedPC	get(Object oid)	Accessor for an object from the cache
int	getSize()	Accessor for the total number of objects in the L2 cache.
boolean	isEmpty()	Accessor for whether the cache is empty.
CachedPC	put(Object oid, CachedPC pc)	Method to put an object in the L2 cache

Methods inherited from class Object

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

Methods inherited from interface Level2Cache

getAll, getNumberOfPinnedObjects, getNumberOfUnpinnedObjects, getUnique, pin, pinAll, pinAll, pinAll, putAll, putUnique, putUniqueAll, removeUnique, unpin, unpinAll, unpinAll, unpinAll

Field Details

NAME

public static final String NAME

See Also:

• Constant Field Values

serialVersionUID

private static final long serialVersionUID

See Also:

• Constant Field Values

Constructor Details

NullLevel2Cache

public NullLevel2Cache(NucleusContext nucleusCtx)

Method Details

close

public void close()

Method to close the cache when no longer needed. Provides a hook to release resources etc.

evict

public void evict(Object oid)

Evict the parameter instance from the second-level cache.

Parameters:

oid - the object id of the instance to evict.

evictAll

public void evictAll()

Evict the parameter instances from the second-level cache. All instances in the PersistenceManager's cache are evicted from the second-level cache.

evictAll

public void evictAll(Class pcClass,
 boolean subclasses)

Evict the parameter instances from the second-level cache.

Parameters:

pcClass - the class to evict

subclasses - Whether to evict all subclasses of this class also

evictAll

public void evictAll(Collection oids)

Evict the parameter instances from the second-level cache.

Parameters:

oids - the object ids of the instance to evict.

evictAll

public void evictAll(Object[] oids)

Evict the parameter instances from the second-level cache.

Parameters:

oids - the object ids of the instances to evict

containsOid

public boolean containsOid(Object oid)

Accessor for whether an object with the specified id is in the cache

Parameters:

oid - The object id

Returns:

Whether it is in the cache

get

public CachedPC get(Object oid)

Accessor for an object from the cache

Parameters:

oid - The identity

Returns:

The cacheable object

getSize

public int getSize()

Description copied from interface: Level2Cache

Accessor for the total number of objects in the L2 cache.

Returns:

Number of objects

See Also:

• Level2Cache.getSize()

isEmpty

public boolean isEmpty()

Description copied from interface: Level2Cache

Accessor for whether the cache is empty.

Returns:

Whether it is empty.

See Also:

• Level2Cache.isEmpty()

put

public CachedPC put(Object oid,
 CachedPC pc)

Method to put an object in the L2 cache

Parameters:

oid - The identity

pc - Cacheable form of the PC

Returns:

Previous value stored for this id