SoftHashMap

java.lang.Object
- java.util.AbstractMap
- - org.onemind.commons.java.lang.ref.SoftHashMap

All Implemented Interfaces:

java.util.Map
```
public class SoftHashMap
extends java.util.AbstractMap
```
Version:

$Id: SoftHashMap.java,v 1.1 2004/10/23 15:24:35 thlee Exp $ $Name: $ Credits: Article by Heinz Kabutz at http://archive.devx.com/java/free/articles/Kabutz01/Kabutz01-1.asp

Author:

TiongHiang Lee (thlee@onemindsoft.org)

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`private static class`	`SoftHashMap.SoftValue` We define our own subclass of SoftReference which contains not only the value but also the key to make it easier to find the entry in the HashMap after it's been garbage collected.

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>

Field Summary

Fields
Modifier and Type	Field and Description
`private int`	`HARD_REF_SIZE` The number of "hard" references to hold internally.
`private java.util.LinkedList`	`hardRefCache` The FIFO list of hard references, order of last access.
`private java.util.Map`	`hash` The internal HashMap that will hold the SoftReference.
`private java.lang.ref.ReferenceQueue`	`queue` Reference queue for cleared SoftReference objects.

Constructor Summary

Constructors
Constructor and Description

SoftHashMap()
Constructor

SoftHashMap(int hardSize)
Constructor

Constructors
Constructor and Description
`SoftHashMap()` Constructor
`SoftHashMap(int hardSize)` Constructor

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`private void`	`_cleanCollectedValues()` Go through the ReferenceQueue and remove garbage collected SoftValue objects from the HashMap
`void`	`clear()`
`java.util.Set`	`entrySet()`
`java.lang.Object`	`get(java.lang.Object key)`
`java.lang.Object`	`put(java.lang.Object key, java.lang.Object value)` Here we put the key, value pair into the HashMap using a SoftValue object.
`java.lang.Object`	`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

- Field Detail
  - hash
```
private final java.util.Map hash
```
    The internal HashMap that will hold the SoftReference.
  - HARD_REF_SIZE
```
private final int HARD_REF_SIZE
```
    The number of "hard" references to hold internally.
  - hardRefCache
```
private final java.util.LinkedList hardRefCache
```
    The FIFO list of hard references, order of last access.
  - queue
```
private final java.lang.ref.ReferenceQueue queue
```
    Reference queue for cleared SoftReference objects.
- Constructor Detail
  - SoftHashMap
```
public SoftHashMap()
```
    Constructor
  - SoftHashMap
```
public SoftHashMap(int hardSize)
```
    Constructor
    
    Parameters:
    
    hardSize - the hard reference size to maintain
- Method Detail
  - get
```
public java.lang.Object get(java.lang.Object key)
```
    Specified by:
    
    get in interface java.util.Map
    
    Overrides:
    
    get in class java.util.AbstractMap
  - _cleanCollectedValues
```
private void _cleanCollectedValues()
```
    Go through the ReferenceQueue and remove garbage collected SoftValue objects from the HashMap
  - put
```
public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)
```
    Here we put the key, value pair into the HashMap using a SoftValue object.
    
    Specified by:
    
    put in interface java.util.Map
    
    Overrides:
    
    put in class java.util.AbstractMap
  - remove
```
public java.lang.Object remove(java.lang.Object key)
```
    Specified by:
    
    remove in interface java.util.Map
    
    Overrides:
    
    remove in class java.util.AbstractMap
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface java.util.Map
    
    Overrides:
    
    clear in class java.util.AbstractMap
  - size
```
public int size()
```
    Specified by:
    
    size in interface java.util.Map
    
    Overrides:
    
    size in class java.util.AbstractMap
  - entrySet
```
public java.util.Set entrySet()
```
    Specified by:
    
    entrySet in interface java.util.Map
    
    Specified by:
    
    entrySet in class java.util.AbstractMap

Class SoftHashMap

Nested Class Summary

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

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

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.util.AbstractMap

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Field Detail

hash

HARD_REF_SIZE

hardRefCache

queue

Constructor Detail

SoftHashMap

SoftHashMap

Method Detail

get

_cleanCollectedValues

put

remove

clear

size

entrySet