com.sun.jmx.remote.opt.util

Class CacheMap

java.lang.Object

java.util.AbstractMap<K,V>

java.util.WeakHashMap

com.sun.jmx.remote.opt.util.CacheMap

All Implemented Interfaces:

Map

public class CacheMap
extends WeakHashMap

Like WeakHashMap, except that the keys of the n most recently-accessed entries are kept as soft references. Accessing an element means creating it, or retrieving it with get. Because these entries are kept with soft references, they will tend to remain even if their keys are not referenced elsewhere. But if memory is short, they will be removed.

Nested Class Summary

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

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

Constructor Summary

Constructors

Constructor and Description
CacheMap(int nSoftReferences) Create a CacheMap that can keep up to nSoftReferences as soft references.

Method Summary

Modifier and Type	Method and Description
Object	get(Object key)
Object	put(Object key, Object value)

Methods inherited from class java.util.WeakHashMap

clear, containsKey, containsValue, entrySet, forEach, isEmpty, keySet, putAll, remove, replaceAll, size, values

Methods inherited from class java.util.AbstractMap

clone, equals, hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

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

Constructor Detail

CacheMap

public CacheMap(int nSoftReferences)

Create a CacheMap that can keep up to nSoftReferences as soft references.

Parameters:

nSoftReferences - Maximum number of keys to keep as soft references. Access times for get and put have a component that scales linearly with nSoftReferences, so this value should not be too great.

Throws:

IllegalArgumentException - if nSoftReferences is negative.

Method Detail

put

public Object put(Object key,
                  Object value)

Specified by:

put in interface Map

Overrides:

put in class WeakHashMap

get

public Object get(Object key)

Specified by:

get in interface Map

Overrides:

get in class WeakHashMap