com.fasterxml.jackson.databind.util

Class LRUMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

java.util.HashMap<K,V>

java.util.LinkedHashMap<K,V>

com.fasterxml.jackson.databind.util.LRUMap<K,V>

All Implemented Interfaces:

Serializable, Cloneable, Map<K,V>

public class LRUMap<K,V>
extends LinkedHashMap<K,V>
implements Serializable

Helper for simple bounded LRU maps used for reusing lookup values.

Note that serialization behavior is such that contents are NOT serialized, on assumption that all use cases are for caching where persistence does not make sense. The only thing serialized is the cache size of Map.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Field Summary

Fields

Modifier and Type	Field and Description
protected int	_jdkSerializeMaxEntries Ugly hack, to work through the requirement that _value is indeed final, and that JDK serialization won't call ctor(s) if Serializable is implemented.
protected int	_maxEntries

Constructor Summary

Constructors

Constructor and Description
LRUMap(int initialEntries, int maxEntries)

Method Summary

Methods

Modifier and Type	Method and Description
protected Object	readResolve()
protected boolean	removeEldestEntry(Map.Entry<K,V> eldest)

Methods inherited from class java.util.LinkedHashMap

clear, containsValue, get

Methods inherited from class java.util.HashMap

clone, containsKey, entrySet, isEmpty, keySet, put, putAll, remove, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

containsKey, entrySet, equals, hashCode, isEmpty, keySet, put, putAll, remove, size, values

Field Detail

_maxEntries

protected final int _maxEntries

_jdkSerializeMaxEntries

protected transient int _jdkSerializeMaxEntries

Ugly hack, to work through the requirement that _value is indeed final, and that JDK serialization won't call ctor(s) if Serializable is implemented.

Since:

2.1

Constructor Detail

LRUMap

public LRUMap(int initialEntries,
      int maxEntries)

Method Detail

removeEldestEntry

protected boolean removeEldestEntry(Map.Entry<K,V> eldest)

Overrides:

removeEldestEntry in class LinkedHashMap<K,V>

readResolve

protected Object readResolve()