org.apache.shenyu.common.cache

Class WindowTinyLFUMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

org.apache.shenyu.common.cache.WindowTinyLFUMap<K,V>

All Implemented Interfaces:

java.io.Serializable, java.util.Map<K,V>

@ThreadSafe
public class WindowTinyLFUMap<K,V>
extends java.util.AbstractMap<K,V>
implements java.io.Serializable

this cache is provided by caffeine, the cache has two implements including weak-key cache and strong-key cache.

the weak-key cache applies to scenarios where objects can be collected. when memory lock causes full gc, the weakKey will collect by gc.

the strong-key cache applies to immutable cache object data, and the user determines the cache size.

about the weak-key cache and strong-key cache, please refer to: caffeine cache ISSUES #776

See Also:

Serialized Form

Nested Class Summary

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

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

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

java.util.Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
WindowTinyLFUMap(int initialCapacity, long maximumSize, java.lang.Boolean weakKey) initial caffeine cache include WeakReference cache and StrongReference cache.
WindowTinyLFUMap(int initialSize, long expireAfterWrite, long maximumSize, java.lang.Boolean weakKey)
WindowTinyLFUMap(long maximumSize) build caffeine cache.

Method Summary

Modifier and Type	Method and Description
void	clear()
java.util.Set<java.util.Map.Entry<K,V>>	entrySet()
V	get(java.lang.Object key)
V	put(K key, V value)
V	remove(java.lang.Object key)
int	size()

Methods inherited from class java.util.AbstractMap

clone, containsKey, containsValue, equals, hashCode, isEmpty, keySet, putAll, toString, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

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

Constructor Detail

WindowTinyLFUMap

public WindowTinyLFUMap(long maximumSize)

build caffeine cache.

Parameters:

maximumSize - maximumSize

WindowTinyLFUMap

public WindowTinyLFUMap(int initialCapacity,
                        long maximumSize,
                        java.lang.Boolean weakKey)

initial caffeine cache include WeakReference cache and StrongReference cache.

when the weakKey is true that means using weakKeys cache, gc will collect the weak key, please refer to: com.github.benmanes.caffeine.cache.References.WeakKeyReference

when the weakKey is false, use strong reference, jvm maybe throw oom-error.

 Map<String, Object> strongMap = new WindowTinyLFUMap<>(100, 100, Boolean.FALSE);
 strongMap.put(new String("abc"), 1);
 strongMap.put(new String("abc"), 1);
 assert strongMap.get("abc") != null;

 Map<String, Object> strongMap = new WindowTinyLFUMap<>(100, 100, Boolean.TRUE);
 strongMap.put(new String("abc"), 1);
 strongMap.put(new String("abc"), 1);
 assert strongMap.get("abc") == null;
 

Parameters:

initialCapacity - initial capacity

maximumSize - maximum size

weakKey - weak key

WindowTinyLFUMap

public WindowTinyLFUMap(int initialSize,
                        long expireAfterWrite,
                        long maximumSize,
                        java.lang.Boolean weakKey)

Method Detail

put

public V put(K key,
             V value)

Specified by:

put in interface java.util.Map<K,V>

Overrides:

put in class java.util.AbstractMap<K,V>

get

public V get(java.lang.Object key)

Specified by:

get in interface java.util.Map<K,V>

Overrides:

get in class java.util.AbstractMap<K,V>

remove

public V remove(java.lang.Object key)

Specified by:

remove in interface java.util.Map<K,V>

Overrides:

remove in class java.util.AbstractMap<K,V>

clear

public void clear()

Specified by:

clear in interface java.util.Map<K,V>

Overrides:

clear in class java.util.AbstractMap<K,V>

size

public int size()

Specified by:

size in interface java.util.Map<K,V>

Overrides:

size in class java.util.AbstractMap<K,V>

entrySet

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

Specified by:

entrySet in interface java.util.Map<K,V>

Specified by:

entrySet in class java.util.AbstractMap<K,V>