Package org.zkoss.util

Class EmptyCacheMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

org.zkoss.util.EmptyCacheMap<K,V>

All Implemented Interfaces:

Map<K,V>, Cache<K,V>

public class EmptyCacheMap<K,V>
extends AbstractMap<K,V>
implements Cache<K,V>

An empty cache map.

Since:

9.6.0

Author:

jameschu

Nested Class Summary

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

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

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

Map.Entry<K extends Object,V extends Object>

Field Summary

Fields inherited from interface org.zkoss.util.Cache

DEFAULT_LIFETIME, DEFAULT_MAX_SIZE

Constructor Summary

Constructors

Constructor	Description
EmptyCacheMap()

Method Summary

Modifier and Type	Method	Description
Set<Map.Entry<K,V>>	entrySet()
int	getLifetime()	Returns the minimal lifetime, unit=milliseconds.
int	getMaxSize()	Returns the maximal allowed size.
V	put(K key, V value)	Stores an object to the cache.
void	setLifetime(int lifetime)	Sets the minimal lifetime.
void	setMaxSize(int maxsize)	Sets the maximal allowed size.

Methods inherited from class java.util.AbstractMap

clear, clone, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, putAll, remove, size, toString, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.zkoss.util.Cache

clear, containsKey, get, remove

Methods inherited from interface java.util.Map

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

Constructor Details

EmptyCacheMap

public EmptyCacheMap()

Method Details

put

public V put(K key,
 V value)

Description copied from interface: Cache

Stores an object to the cache.

Specified by:

put in interface Cache<K,V>

Specified by:

put in interface Map<K,V>

Overrides:

put in class AbstractMap<K,V>

Returns:

the previous value of the same, or null if no such value

getLifetime

public int getLifetime()

Description copied from interface: Cache

Returns the minimal lifetime, unit=milliseconds. An mapping won't be removed by GC unless the minimal lifetime or the maximal allowed size exceeds.

Specified by:

getLifetime in interface Cache<K,V>

See Also:

• Cache.getMaxSize()

setLifetime

public void setLifetime(int lifetime)

Description copied from interface: Cache

Sets the minimal lifetime. Default: Cache.DEFAULT_LIFETIME.

Specified by:

setLifetime in interface Cache<K,V>

Parameters:

lifetime - the lifetime, unit=milliseconds; if non-positive, they will be removed immediately.

See Also:

• Cache.getLifetime()

getMaxSize

public int getMaxSize()

Description copied from interface: Cache

Returns the maximal allowed size. Default: Cache.DEFAULT_MAX_SIZE. An mapping won't be removed by GC unless the minimal lifetime or the maximal allowed size exceeds.

Specified by:

getMaxSize in interface Cache<K,V>

See Also:

• Cache.getLifetime()

setMaxSize

public void setMaxSize(int maxsize)

Description copied from interface: Cache

Sets the maximal allowed size.

Specified by:

setMaxSize in interface Cache<K,V>

See Also:

• Cache.getMaxSize()

entrySet

public Set<Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface Map<K,V>

Specified by:

entrySet in class AbstractMap<K,V>