Packagespark.core
Classpublic class ContentCache
InheritanceContentCache Inheritance flash.events.EventDispatcher
Implements IContentLoader

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Provides a caching and queuing image content loader suitable for using a shared image cache for the BitmapImage and spark Image components.


Public Properties
 PropertyDefined By
  enableCaching : Boolean
Enables caching behavior and functionality.
ContentCache
  enableQueueing : Boolean
Enables queuing behavior and functionality.
ContentCache
  maxActiveRequests : int
Maximum simultaneous active requests when queuing is enabled.
ContentCache
  maxCacheEntries : int
Maximum size of MRU based cache.
ContentCache
  numCacheEntries : int
[read-only] Count of active/in-use cache entries.
ContentCache
Protected Properties
 PropertyDefined By
  activeRequests : LinkedList
List of queued CacheEntryNode instances currently executing.
ContentCache
  cachedData : Dictionary
Map of source to CacheEntryNode.
ContentCache
  cacheEntries : LinkedList
Ordered (MRU) list of CacheEntryNode instances.
ContentCache
  priorityGroup : String = _DEFAULT_
Identifier of the currently prioritized content grouping.
ContentCache
  requestQueue : LinkedList
List of queued CacheEntryNode instances.
ContentCache
Public Methods
 MethodDefined By
  
ContentCache()
Constructor.
ContentCache
  
addCacheEntry(source:Object, value:Object):void
Adds new entry to cache (or replaces existing entry).
ContentCache
  
getCacheEntry(source:Object):Object
Obtain an entry for the given key if one exists.
ContentCache
  
load(source:Object, contentLoaderGrouping:String = null):ContentRequest
Initiates a content request for the resource identified by the key specified.
ContentCache
  
prioritize(contentLoaderGrouping:String):void
Promotes a content grouping to the head of the loading queue.
ContentCache
  
removeAllCacheEntries():void
Resets our cache content to initial empty state.
ContentCache
  
removeAllQueueEntries():void
Resets the queue to initial empty state.
ContentCache
  
removeCacheEntry(source:Object):void
Remove specific entry from cache.
ContentCache
Events
 Event Summary Defined By
  
invalidateLoader
Dispatched when a cache entry is invalidated, generally this occurs when the entry is determined to be untrusted while one or more outstanding load requests are active for a given cache entry.ContentCache
Protected Constants
 ConstantDefined By
  UNTRUSTED : String = untrusted
[static] Value used to mark cached URLs that are detected as being from an untrusted source (meaning they will no longer be shareable).
ContentCache
Property Detail
activeRequestsproperty
protected var activeRequests:LinkedList

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

List of queued CacheEntryNode instances currently executing.

cachedDataproperty 
protected var cachedData:Dictionary

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Map of source to CacheEntryNode.

cacheEntriesproperty 
protected var cacheEntries:LinkedList

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Ordered (MRU) list of CacheEntryNode instances.

enableCachingproperty 
enableCaching:Boolean

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Enables caching behavior and functionality. Applies only to new load() requests.

The default value is true.


Implementation
    public function get enableCaching():Boolean
    public function set enableCaching(value:Boolean):void
enableQueueingproperty 
enableQueueing:Boolean

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Enables queuing behavior and functionality. Applies only to new load() requests.

The default value is false.


Implementation
    public function get enableQueueing():Boolean
    public function set enableQueueing(value:Boolean):void
maxActiveRequestsproperty 
maxActiveRequests:int

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Maximum simultaneous active requests when queuing is enabled.

The default value is 2.


Implementation
    public function get maxActiveRequests():int
    public function set maxActiveRequests(value:int):void
maxCacheEntriesproperty 
maxCacheEntries:int

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Maximum size of MRU based cache. When numCacheEntries exceeds maxCacheEntries the least recently used are pruned to fit.

The default value is 100.


Implementation
    public function get maxCacheEntries():int
    public function set maxCacheEntries(value:int):void
numCacheEntriesproperty 
numCacheEntries:int  [read-only]

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Count of active/in-use cache entries.


Implementation
    public function get numCacheEntries():int
priorityGroupproperty 
protected var priorityGroup:String = _DEFAULT_

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Identifier of the currently prioritized content grouping.

The default value is "_DEFAULT_".

requestQueueproperty 
protected var requestQueue:LinkedList

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

List of queued CacheEntryNode instances.

Constructor Detail
ContentCache()Constructor
public function ContentCache()

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Constructor.

Method Detail
addCacheEntry()method
public function addCacheEntry(source:Object, value:Object):void

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Adds new entry to cache (or replaces existing entry).

Parameters

source:Object — Unique key to associate provided value with in cache.
 
value:Object — Value to cache for given key.

getCacheEntry()method 
public function getCacheEntry(source:Object):Object

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Obtain an entry for the given key if one exists.

Parameters

source:Object — Unique key used to represent the requested content resource.

Returns
Object — A value being stored by the cache for the provided key. Returns null if not found or in the likely case the value was stored as null.
load()method 
public function load(source:Object, contentLoaderGrouping:String = null):ContentRequest

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 2.5

Initiates a content request for the resource identified by the key specified.

Parameters

source:Object — Unique key used to represent the requested content resource. This parameter is typically an URL or URLRequest.
 
contentLoaderGrouping:String (default = null) — - (Optional) grouping identifier for the loaded resource. ContentLoader instances supporting content groups generally allow for resources within the same named grouping to be addressed as a whole. For example the ContentCache's loader queue allows requests to be prioritized by contentLoaderGrouping.

Returns
ContentRequest — A ContentRequest instance representing the requested resource.
prioritize()method 
public function prioritize(contentLoaderGrouping:String):void

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Promotes a content grouping to the head of the loading queue.

Parameters

contentLoaderGrouping:String — Name of content grouping to promote in the loading queue. All queued requests with matching contentLoaderGroup will be shifted to the head of the queue.

removeAllCacheEntries()method 
public function removeAllCacheEntries():void

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Resets our cache content to initial empty state.

removeAllQueueEntries()method 
public function removeAllQueueEntries():void

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Resets the queue to initial empty state. All requests, both active and queued, are cancelled. All cache entries associated with canceled requests are invalidated.

removeCacheEntry()method 
public function removeCacheEntry(source:Object):void

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 1.5

Remove specific entry from cache.

Parameters

source:Object — Unique key for value to remove from cache.

Event Detail
invalidateLoader Event
Event Object Type: spark.events.LoaderInvalidationEvent
LoaderInvalidationEvent.type property = spark.events.LoaderInvalidationEvent

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 10, AIR 2.0

Dispatched when a cache entry is invalidated, generally this occurs when the entry is determined to be untrusted while one or more outstanding load requests are active for a given cache entry. This mechanism allows any outstanding content requests to be reset due to the fact that the cache entry has been deemed 'unshareable'. Each content request notified then attempts instead re-requests the asset.

Constant Detail
UNTRUSTEDConstant
protected static const UNTRUSTED:String = untrusted

Language Version : ActionScript 3.0
Product Version : Flex 4.5
Runtime Versions : Flash Player 9, AIR 1.1

Value used to mark cached URLs that are detected as being from an untrusted source (meaning they will no longer be shareable).





Mon Dec 24 2012, 01:18 PM +11:00