com.technia.tvc.core.util

Class SoftMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

com.technia.tvc.core.util.SoftMap<K,V>

All Implemented Interfaces:

java.util.Map<K,V>

public class SoftMap<K,V>
extends java.util.AbstractMap<K,V>
implements java.util.Map<K,V>

This class cache objects in a map using soft references. This means that when there are no strong references pointing to an object stored in this map it is up to the garbage collector to finalize the object.

When the object has been finalized it will no longer be available in this map and the soft reference pointing to the object will be removed. But until the object is finalized it is possible to get a strong reference to it.

Use this class to minimize the use of memory when caching object instances since it is specified that all soft references are cleared and finalized before the JVM raises an java.lang.OutOfMemoryError.

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
SoftMap() No argument constructor.
SoftMap(int i) Constructs a soft cache map with the specified initial capacity.
SoftMap(int i, float f) Constructs a soft cache map with the specified initial capacity and load factor.

Method Summary

Modifier and Type	Method and Description
void	clear() Clears the map.
boolean	containsKey(java.lang.Object obj) Returns true if the map contains the specified key.
java.util.Set<java.util.Map.Entry<K,V>>	entrySet() Returns the entry set.
protected V	fill(java.lang.Object obj) Does nothing.
V	get(java.lang.Object obj) Returns the object bound to the specified key.
boolean	isEmpty() Returns true if the map is empty.
V	put(K key, V value) Puts the specified value in the map bound to the specified key.
V	remove(java.lang.Object obj) Removes the object bound to the specified key.
int	size() Returns the size of the map.

Methods inherited from class java.util.AbstractMap

clone, containsValue, equals, hashCode, 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, containsValue, equals, forEach, getOrDefault, hashCode, keySet, merge, putAll, putIfAbsent, remove, replace, replace, replaceAll, values

Constructor Detail

SoftMap

public SoftMap(int i,
               float f)

Constructs a soft cache map with the specified initial capacity and load factor.

SoftMap

public SoftMap(int i)

Constructs a soft cache map with the specified initial capacity.

SoftMap

public SoftMap()

No argument constructor.

Method Detail

size

public int size()

Returns the size of the map.

Specified by:

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

Overrides:

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

isEmpty

public boolean isEmpty()

Returns true if the map is empty.

Specified by:

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

Overrides:

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

containsKey

public boolean containsKey(java.lang.Object obj)

Returns true if the map contains the specified key.

Specified by:

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

Overrides:

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

fill

protected V fill(java.lang.Object obj)

Does nothing.

get

public V get(java.lang.Object obj)

Returns the object bound to the specified key.

Specified by:

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

Overrides:

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

put

public V put(K key,
             V value)

Puts the specified value in the map bound to the specified key.

Specified by:

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

Overrides:

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

remove

public V remove(java.lang.Object obj)

Removes the object bound to the specified key.

Specified by:

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

Overrides:

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

clear

public void clear()

Clears the map.

Specified by:

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

Overrides:

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

entrySet

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

Returns the entry set.

Specified by:

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

Specified by:

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