Package org.datanucleus.cache

Class WeakRefCache

java.lang.Object

org.datanucleus.cache.WeakRefCache

All Implemented Interfaces:

java.util.Map<java.lang.Object,DNStateManager>, Level1Cache

public class WeakRefCache
extends java.lang.Object
implements Level1Cache

Level 1 Cache using Weak referenced objects in a Map. If the garbage collector clears the reference, the corresponding key is automatically removed from the map.

See Also:

WeakReference

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

java.util.Map.Entry<K extends java.lang.Object,V extends java.lang.Object>

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	NAME
private java.util.Map<java.lang.Object,DNStateManager>	weakCache
private java.util.Map<CacheUniqueKey,DNStateManager>	weakCacheUnique

Fields inherited from interface org.datanucleus.cache.Level1Cache

NONE_NAME

Constructor Summary

Constructors

Constructor	Description
WeakRefCache()	Default constructor (required)

Method Summary

Modifier and Type	Method	Description
void	clear()
boolean	containsKey(java.lang.Object id)
boolean	containsValue(java.lang.Object value)
java.util.Set	entrySet()
DNStateManager	get(java.lang.Object id)
DNStateManager	getUnique(CacheUniqueKey key)	Method to retrieve StateManager for the specified unique key.
boolean	isEmpty()
java.util.Set	keySet()
DNStateManager	put(java.lang.Object id, DNStateManager sm)
void	putAll(java.util.Map t)
java.lang.Object	putUnique(CacheUniqueKey key, DNStateManager sm)	Method to store a StateManager for this unique key.
DNStateManager	remove(java.lang.Object id)
int	size()
java.util.Collection	values()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Field Detail

NAME

public static final java.lang.String NAME

See Also:

Constant Field Values

weakCache

private java.util.Map<java.lang.Object,DNStateManager> weakCache

weakCacheUnique

private java.util.Map<CacheUniqueKey,DNStateManager> weakCacheUnique

Constructor Detail

WeakRefCache

public WeakRefCache()

Default constructor (required)

Method Detail

put

public DNStateManager put(java.lang.Object id,
                          DNStateManager sm)

Specified by:

put in interface java.util.Map<java.lang.Object,DNStateManager>

get

public DNStateManager get(java.lang.Object id)

Specified by:

get in interface java.util.Map<java.lang.Object,DNStateManager>

containsKey

public boolean containsKey(java.lang.Object id)

Specified by:

containsKey in interface java.util.Map<java.lang.Object,DNStateManager>

remove

public DNStateManager remove(java.lang.Object id)

Specified by:

remove in interface java.util.Map<java.lang.Object,DNStateManager>

clear

public void clear()

Specified by:

clear in interface java.util.Map<java.lang.Object,DNStateManager>

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

containsValue in interface java.util.Map<java.lang.Object,DNStateManager>

entrySet

public java.util.Set entrySet()

Specified by:

entrySet in interface java.util.Map<java.lang.Object,DNStateManager>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Map<java.lang.Object,DNStateManager>

keySet

public java.util.Set keySet()

Specified by:

keySet in interface java.util.Map<java.lang.Object,DNStateManager>

putAll

public void putAll(java.util.Map t)

Specified by:

putAll in interface java.util.Map<java.lang.Object,DNStateManager>

size

public int size()

Specified by:

size in interface java.util.Map<java.lang.Object,DNStateManager>

values

public java.util.Collection values()

Specified by:

values in interface java.util.Map<java.lang.Object,DNStateManager>

getUnique

public DNStateManager getUnique(CacheUniqueKey key)

Description copied from interface: Level1Cache

Method to retrieve StateManager for the specified unique key.

Specified by:

getUnique in interface Level1Cache

Parameters:

key - Unique key

Returns:

StateManager if one is cached for this unique key

putUnique

public java.lang.Object putUnique(CacheUniqueKey key,
                                  DNStateManager sm)

Description copied from interface: Level1Cache

Method to store a StateManager for this unique key.

Specified by:

putUnique in interface Level1Cache

Parameters:

key - The unique key

sm - StateManager

Returns:

The previous StateManager for this unique key if one was present, otherwise null