WeakReferenceContainer (Castor 1.3.2 API)

java.lang.Object
- org.castor.cache.hashbelt.container.WeakReferenceContainer

All Implemented Interfaces:

Map<Object,Object>, Container
```
public final class WeakReferenceContainer
extends Object
implements Container
```
An implementation of a container that uses weak references for storing values in the map, so that values can be removed from the map by the system when the system is under memory pressure. Keys, however, are kept strong - so contains() may well find an element, but the value may have been lost. Make sure you test for null returns from put.
Note that keys are hard references; in a situation where OutOfMemory will occur, the JVM will first wipe out all unreferenced objects whose only link is a weak reference. An out of memory will wipe all values from the maps which are currently unreferenced. The keys remain until the hashbelt containers are garbage collected, an put is called with that key or when the value should be accessed through any operation of the Container interface.

Since:

1.0

Version:

$Revision: 8102 $ $Date: 2006-04-25 16:09:10 -0600 (Tue, 25 Apr 2006) $

Author:

Gregory Block, Ralf Joachim

Nested Class Summary
- Nested classes/interfaces inherited from interface java.util.Map
  Map.Entry<K,V>

Constructor Summary

Constructors
Constructor and Description

WeakReferenceContainer()

Constructors
Constructor and Description
`WeakReferenceContainer()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clear()`
`boolean`	`containsKey(Object key)`
`boolean`	`containsValue(Object value)`
`Set<Map.Entry<Object,Object>>`	`entrySet()`
`Object`	`get(Object key)`
`long`	`getTimestamp()` Returns the timestamp of this container.
`boolean`	`isEmpty()`
`Iterator<Object>`	`keyIterator()` Returns an iterator over the keys contained in this container.
`Set<Object>`	`keySet()`
`Object`	`put(Object key, Object value)`
`void`	`putAll(Map<? extends Object,? extends Object> map)`
`Object`	`remove(Object key)`
`int`	`size()`
`void`	`updateTimestamp()` Set the timestamp of this container to System.currentTimeMillis().
`Iterator<Object>`	`valueIterator()` Returns an iterator over the values contained in this container.
`Collection<Object>`	`values()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

- Constructor Detail
  - WeakReferenceContainer
```
public WeakReferenceContainer()
```
- Method Detail
  - updateTimestamp
```
public void updateTimestamp()
```
    Set the timestamp of this container to System.currentTimeMillis().
    
    Specified by:
    
    updateTimestamp in interface Container
  - getTimestamp
```
public long getTimestamp()
```
    Returns the timestamp of this container.
    
    Specified by:
    
    getTimestamp in interface Container
    
    Returns:
    
    The timestamp.
  - keyIterator
```
public Iterator<Object> keyIterator()
```
    Returns an iterator over the keys contained in this container. If the container is modified while an iteration is in progress, the results of the iteration is not affected and vice-versa.
    
    Specified by:
    
    keyIterator in interface Container
    
    Returns:
    
    An iterator over the keys currently contained in the container.
  - valueIterator
```
public Iterator<Object> valueIterator()
```
    Returns an iterator over the values contained in this container. If the container is modified while an iteration is in progress, the results of the iteration is not affected and vice-versa.
    
    Specified by:
    
    valueIterator in interface Container
    
    Returns:
    
    An iterator over the values currently contained in the container.
  - size
```
public int size()
```
    Specified by:
    
    size in interface Map<Object,Object>
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface Map<Object,Object>
  - containsKey
```
public boolean containsKey(Object key)
```
    Specified by:
    
    containsKey in interface Map<Object,Object>
  - containsValue
```
public boolean containsValue(Object value)
```
    Specified by:
    
    containsValue in interface Map<Object,Object>
  - get
```
public Object get(Object key)
```
    Specified by:
    
    get in interface Map<Object,Object>
  - put
```
public Object put(Object key,
                  Object value)
```
    Specified by:
    
    put in interface Map<Object,Object>
  - remove
```
public Object remove(Object key)
```
    Specified by:
    
    remove in interface Map<Object,Object>
  - putAll
```
public void putAll(Map<? extends Object,? extends Object> map)
```
    Specified by:
    
    putAll in interface Map<Object,Object>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface Map<Object,Object>
  - keySet
```
public Set<Object> keySet()
```
    Specified by:
    
    keySet in interface Map<Object,Object>
  - values
```
public Collection<Object> values()
```
    Specified by:
    
    values in interface Map<Object,Object>
  - entrySet
```
public Set<Map.Entry<Object,Object>> entrySet()
```
    Specified by:
    
    entrySet in interface Map<Object,Object>

Class WeakReferenceContainer

Nested Class Summary

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

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Constructor Detail

WeakReferenceContainer

Method Detail

updateTimestamp

getTimestamp

keyIterator

valueIterator

size

isEmpty

containsKey

containsValue

get

put

remove

putAll

clear

keySet

values

entrySet