Adobe® Flex® 4 Language Reference
Hide Packages and Classes List |  Packages  |  Classes  |  Index  |  Appendixes
mx.data 
RPCDataServiceAdapter 
Packagemx.data
Classpublic class RPCDataServiceAdapter
InheritanceRPCDataServiceAdapter Inheritance DataServiceAdapter Inheritance Object

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This is the abstract base class which you use to implement a new type of DataService implementation. Extend this class and override methods such as createItem, updateItem, etc. to customize how those calls are implemented. DataManagement will call these methods automatically as needed.

The trickiest thing about how this service works is that we want to take over the existing service's invocation so that user code is minimally impacted by the addition of data management. The service call works the same way, same events and tokens are fired only the result must be managed. To make this work, the RPCDataServiceAdapter associated a ManagedOperation with a regular RPC service operation. The operation's "operationManager" property is set and during initialization time and the end-user's call is redirected to a proxy method in this class (e.g. queryProxy). This generates the corresponding data management call and returns the managed token to the end user so they get the result of the managed operation.

 order is:
  user calls service method
     calls service delegates to operationManager - ManagedOpertion.xxProxy methods
        calls managerOperation kicks off DMS op --> DataManager.xx
           calls DMS op calls adapter to do the op --> DataServiceAdapter.invoke
              calls: RPCDataServiceAdapter invokes the service operation and sets the "raw" lastResult
              returns: adapter's result comes back in and is converted to DMS Result Message - RPCDataServiceResult.xxResult
        returns: data manager processes result - updates managed object --> DataListRequestResponder/CommitResponder
     returns: service is updated to lastResult from the operation
  returns: user's result event is called
 



Public Properties
 PropertyDefined By
  asyncRequest : AsyncRequest
[override] [read-only] An abstract method which returns an AsyncRequest that is used to handle all DataService operations.
RPCDataServiceAdapter
 Inheritedconnected : Boolean
[read-only] Returns true when this service adapter is connected to its source.
DataServiceAdapter
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  dataManagerRegistry : Object
[static] Static map from destination name to data manager for that destination.
RPCDataServiceAdapter
 InheriteddataStore : DataStore
Contains an object of type mx.data.DataStore.
DataServiceAdapter
  destination : String
Name of destination for this data service adapter.
RPCDataServiceAdapter
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  serializeAssociations : Boolean
[override] [read-only] This controls whether or not DMS wraps the items into a serialization descriptor which excludes the associations.
RPCDataServiceAdapter
  throwUnhandledFaults : Boolean
[override] [read-only] Returns false because this data manager does not throw an error if there is a fault with no listeners on the data manager.
RPCDataServiceAdapter
Public Methods
 MethodDefined By
  
This method is called by the RPCDataServiceAdapter when it needs to perform the createItem operation.
RPCDataServiceAdapter
  
This is called by the RPCDataServiceAdapter when the management layer wants to delete an item from the server.
RPCDataServiceAdapter
  
executeQuery(dataManager:RPCDataManager, queryName:String, includeSpecifier:PropertySpecifier, queryArgs:Array):mx.rpc:AsyncToken
Called when the adapter needs to execute a named query.
RPCDataServiceAdapter
  
Returns an array of property names that conflict between the client's version of an item and the server's version.
RPCDataServiceAdapter
  
[override]
RPCDataServiceAdapter
 Inherited
Looks up an associated data service adapter.
DataServiceAdapter
  
getItem(dataManager:RPCDataManager, identity:Object, defaultValue:Object = null, includeSpecifier:PropertySpecifier = null):mx.rpc:AsyncToken
Called to retrieve an individual item by identity from the adapter.
RPCDataServiceAdapter
  
getItems(dataManager:RPCDataManager, ids:Array, includeSpecifier:PropertySpecifier):mx.rpc:AsyncToken
Adapter method called when a list of items for a specific destination need to be fetched.
RPCDataServiceAdapter
  
This gets called after we've finished processing a fault of a create, update, delete, or update collection operation.
RPCDataServiceAdapter
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
  
pageQuery(dataManager:RPCDataManager, queryName:String, queryArgs:Array, startIndex:int, numItems:int):mx.rpc:AsyncToken
Perform a query for a single page of a client side query.
RPCDataServiceAdapter
  
Low-level method used by the DataManager to processes a data message.
RPCDataServiceAdapter
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
  
This gets called when we get a fault that might be a conflict from the server.
RPCDataServiceAdapter
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
  
This is called when a collection managed by a query (not an association) has items added to the collection or removed from the collection.
RPCDataServiceAdapter
  
updateItem(dataManager:RPCDataManager, item:Object, origItem:Object, changes:Array):mx.rpc:AsyncToken
This method is called by the RPCDataServiceAdapter to perform a specific updateItem operation.
RPCDataServiceAdapter
 Inherited
Returns the primitive value of the specified object.
Object
Protected Methods
 MethodDefined By
  
This method gets called after a fault which might determine a conflict.
RPCDataServiceAdapter
  
internalGetItem(dataManager:RPCDataManager, identity:Object, defaultValue:Object = null, includeSpecifier:PropertySpecifier = null):mx.rpc:AsyncToken
This method actually performs the getItem operation but the result handler will not be used to update the managed result.
RPCDataServiceAdapter
  
Fault responder for RPCDataService operations.
RPCDataServiceAdapter
  
Success responder for RPCDataService operations.
RPCDataServiceAdapter
Property Detail

asyncRequest

property
asyncRequest:AsyncRequest  [read-only] [override]

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

An abstract method which returns an AsyncRequest that is used to handle all DataService operations. By overriding the AsyncRequest.invoke method you can intercept managed requests. The AsyncRequest class also exposes the various methods for determining if the service is connected or disconnected.



Implementation
    override public function get asyncRequest():AsyncRequest

dataManagerRegistry

property 
public static var dataManagerRegistry:Object

Static map from destination name to data manager for that destination.

destination

property 
public var destination:String

Name of destination for this data service adapter.

serializeAssociations

property 
serializeAssociations:Boolean  [read-only] [override]

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This controls whether or not DMS wraps the items into a serialization descriptor which excludes the associations. The MessagingDataServiceAdapter will use this approach for sending associations - not used in the RPCDataServiceAdapter.



Implementation
    override public function get serializeAssociations():Boolean

throwUnhandledFaults

property 
throwUnhandledFaults:Boolean  [read-only] [override]

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Returns false because this data manager does not throw an error if there is a fault with no listeners on the data manager. For RPC servies, those errors are proxied to listeners on the service and so throwing the error is not appropriate.



Implementation
    override public function get throwUnhandledFaults():Boolean
Method Detail

checkForConflict

()method
protected function checkForConflict(resultEvent:ResultEvent, token:mx.rpc:AsyncToken):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This method gets called after a fault which might determine a conflict. In the fault handler for that fault, issue a getItem() call to retrieve the server's current version of the item.

One reason you might want to override this method is if you need to take action after no conflict is detected.

Parameters

resultEvent:ResultEvent — The event object from the getItem() call.
 
token:mx.rpc:AsyncToken — Contains a cause property which is the original DataMessage for the change. This method can call Conflicts.raiseConflict() when there is a conflict, or it can do nothing if it determines there is no conflict.

createItem

()method 
public function createItem(dataManager:RPCDataManager, item:Object):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This method is called by the RPCDataServiceAdapter when it needs to perform the createItem operation. The default implementation is to invoke the managed operation registered for the createItem operation using the item as the first parameter. If you need to invoke more than one service or change the parameter signature for this operation, you can extend the RPCDataServiceAdapter and override this createItem method.

Parameters

dataManager:RPCDataManager — manager in control of the create operation to be invoked.
 
item:Object — item to be created.

Returns
mx.rpc:AsyncToken — You can use this token to register one or more callback functions to receive result or fault events from this create operation. This token is also returned in the call property of the ResultEvent.RESULT or in the FaultEvent.FAULT. Custom data can be attached to this object and inspected later during the event handling phase.

deleteItem

()method 
public function deleteItem(dataManager:RPCDataManager, item:Object):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This is called by the RPCDataServiceAdapter when the management layer wants to delete an item from the server. The item to be deleted is provided as an argument. The default implementation of this method looks for a ManagedOperation of type="delete". That method is called with the item to be deleted, or the id of the item to be deleted if the parameters of the ManagedOperation is set to "id".

Parameters

dataManager:RPCDataManager — manager in control of the delete operation to be invoked.
 
item:Object — item to be deleted.

Returns
mx.rpc:AsyncToken — You can use this token to register one or more callback functions to receive result or fault events from this delete operation. This token is also returned in the call property of the ResultEvent.RESULT or in the FaultEvent.FAULT. Custom data can be attached to this object and inspected later during the event handling phase.

executeQuery

()method 
public function executeQuery(dataManager:RPCDataManager, queryName:String, includeSpecifier:PropertySpecifier, queryArgs:Array):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Called when the adapter needs to execute a named query. If paging is enabled, this will fetch the first page in the collection.

Parameters

dataManager:RPCDataManager — manager in control of the query operation to be invoked.
 
queryName:String — query name
 
includeSpecifier:PropertySpecifier — set of properties to be retrieved.
 
queryArgs:Array — arguments to the query operation invocation.

Returns
mx.rpc:AsyncToken — You can use this token to register one or more callback functions to receive result or fault events from this query operation. This token is also returned in the call property of the ResultEvent.RESULT or in the FaultEvent.FAULT. Custom data can be attached to this object and inspected later during the event handling phase.

getConflictingProperties

()method 
public function getConflictingProperties(dmgr:RPCDataManager, cause:DataMessage, serverObject:Object):Array

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Returns an array of property names that conflict between the client's version of an item and the server's version. Returns null if there are no conflicts.

Parameters

dmgr:RPCDataManager — associated data manager.
 
cause:DataMessage — data message whose processing may have triggered a conflict.
 
serverObject:Object — the server's version of the item.

Returns
Array — an array of property names that conflict between the client's version of an item and the server's version. Returns null if there are no conflicts.

getDataManager

()method 
override public function getDataManager(destination:String):DataManager

Parameters

destination:String

Returns
DataManager

getItem

()method 
public function getItem(dataManager:RPCDataManager, identity:Object, defaultValue:Object = null, includeSpecifier:PropertySpecifier = null):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Called to retrieve an individual item by identity from the adapter. The includeSpecifier parameter specifies the set of properties requested.

Parameters

dataManager:RPCDataManager — associated data manager.
 
identity:Object — identity of the item to be retrieved.
 
defaultValue:Object (default = null) — [optional] An instance of the type with the default values that should be created if it doesn't exist.
 
includeSpecifier:PropertySpecifier (default = null) — [optional] set of properties to be retrieved.

Returns
mx.rpc:AsyncToken — AsyncToken bind to the result property of the AsyncToken to retrieve the result. Otherwise, you can listen for the result property change event, add one or more responders to the token and add additional information as dynamic properties of the token to keep track of the results of the operation.

getItems

()method 
public function getItems(dataManager:RPCDataManager, ids:Array, includeSpecifier:PropertySpecifier):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Adapter method called when a list of items for a specific destination need to be fetched. The PropertySpecifier indicates the minimum set of properties needed. The default implementation of this method is to call the getItem method repeatedly. If your server can perform this operation more efficiently it may improve some operations to implement this method.

Parameters

dataManager:RPCDataManager — associated data manager.
 
ids:Array — [optional] set of properties to be retrieved.
 
includeSpecifier:PropertySpecifier

Returns
mx.rpc:AsyncToken — AsyncToken bind to the result property of the AsyncToken to retrieve the result. Otherwise, you can listen for the result property change event, add one or more responders to the token and add additional information as dynamic properties of the token to keep track of the results of the operation.

handleFault

()method 
public function handleFault(errMsg:ErrorMessage, cause:DataMessage):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This gets called after we've finished processing a fault of a create, update, delete, or update collection operation. It is an adapter's chance to customize logic associated with the error handling and check for conflicts. The default implementation implements the RPCDataManager conflictMode feature. When it gets a fault for an UPDATE or DELETE operation, it compares the current server version against the original version of the updated/deleted object. If the server version is different, we raise that as a conflict. This assumes that the faulting change has already been put back into the uncommitted batch of changes.

Parameters

errMsg:ErrorMessage — The description of the error.
 
cause:DataMessage — The operation that caused the error.

internalGetItem

()method 
protected function internalGetItem(dataManager:RPCDataManager, identity:Object, defaultValue:Object = null, includeSpecifier:PropertySpecifier = null):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This method actually performs the getItem operation but the result handler will not be used to update the managed result. This method is used by the default getItem implementation to invoke the operation. When conflict detection is enabled, after a fault is received for an update or delete operation, this method is called to retrieve the current server version of the object so we can see if the fault was an indication a conflict and to get the current server version so we can resolve that conflict.

Parameters

dataManager:RPCDataManager — associated data manager.
 
identity:Object — identity of the item to be retrieved.
 
defaultValue:Object (default = null) — [optional] An instance of the type with the default values that should be created if it doesn't exist.
 
includeSpecifier:PropertySpecifier (default = null) — [optional] set of properties to be retrieved.

Returns
mx.rpc:AsyncToken — AsyncToken bind to the result property of the AsyncToken to retrieve the result. Otherwise, you can listen for the result property change event, add one or more responders to the token and add additional information as dynamic properties of the token to keep track of the results of the operation.

pageQuery

()method 
public function pageQuery(dataManager:RPCDataManager, queryName:String, queryArgs:Array, startIndex:int, numItems:int):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Perform a query for a single page of a client side query. This method is called when pagingEnabled is set on a ManagedQuery. The client code will invoke the query as normal with just the usual query parameters. The management layer will insert the startIndex and numItems parameters before it makes the call.

Parameters

dataManager:RPCDataManager — manager in control of the query operation to be invoked.
 
queryName:String — query name.
 
queryArgs:Array — arguments to the query operation invocation.
 
startIndex:int — start index for the page to be retrieved.
 
numItems:int — size of page.

Returns
mx.rpc:AsyncToken — You can use this token to register one or more callback functions to receive result or fault events from this query operation. This token is also returned in the call property of the ResultEvent.RESULT or in the FaultEvent.FAULT. Custom data can be attached to this object and inspected later during the event handling phase.

processDataMessage

()method 
public function processDataMessage(msg:IMessage, responder:IResponder):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Low-level method used by the DataManager to processes a data message. It converts the data message into calls to the adpater interface so typically you can override one of those operations.

Parameters

msg:IMessage — message to be processed.
 
responder:IResponder — responder to be called back when the message processing completes.

rpcAdapterFault

()method 
protected function rpcAdapterFault(ev:FaultEvent, token:mx.rpc:AsyncToken):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Fault responder for RPCDataService operations. Handles faults by building appropriate error message and propagating it up the token's responder chain.

Parameters

ev:FaultEvent — fault event received from the server.
 
token:mx.rpc:AsyncToken — token associated with the invocation.

sendResultEvent

()method 
protected function sendResultEvent(token:mx.rpc:AsyncToken, msg:IMessage):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

Success responder for RPCDataService operations. Wraps the received message in a message event and propagates it up the token's responder chain.

Parameters

token:mx.rpc:AsyncToken — token associated with the invocation.
 
msg:IMessage — result message received from the server

startCheckForConflict

()method 
public function startCheckForConflict(dmgr:RPCDataManager, cause:DataMessage):void

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This gets called when we get a fault that might be a conflict from the server. We'll try to get the current values for the item which is in conflict and then compare them to the original item in the change we tried to apply. If there are differences, that is a conflict which we'll raise.

Parameters

dmgr:RPCDataManager — the data manager associated with this adapter's destination.
 
cause:DataMessage — original data message that may have potentially caused a conflict.

updateCollection

()method 
public function updateCollection(dataManager:RPCDataManager, mq:ManagedQuery, ucmsg:UpdateCollectionMessage):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This is called when a collection managed by a query (not an association) has items added to the collection or removed from the collection. There is a single message with a list of individual changes. Often you do not need to override this method as those changes are not needed to persist changes made on the client.

If you are implementing associations such as a many-to-many relationship using queries, it may be helpful though to add/remove a row during these operations.

The RPCDataServiceAdapter implementation maps these to individual add and remove calls.

Parameters

dataManager:RPCDataManager — The data manager associated with this adapter's destination.
 
mq:ManagedQuery — the managed query for which items have been added or removed.
 
ucmsg:UpdateCollectionMessage — update collection message detailing the items that have been added or removed

Returns
mx.rpc:AsyncToken — AsyncToken reference to the token that will identify this operation in a result or fault event dispatched from this service.

updateItem

()method 
public function updateItem(dataManager:RPCDataManager, item:Object, origItem:Object, changes:Array):mx.rpc:AsyncToken

Language Version: ActionScript 3.0
Product Version: LiveCycle Data Services 3
Runtime Versions: Flash Player 9, AIR 1.1

This method is called by the RPCDataServiceAdapter to perform a specific updateItem operation. It is given the new version of the item, the original version of that item before it was modified on this client and the list of properties which are changed. The default implementation looks for a ManagedOperation of type="update" and calls that. The managed operation should at least take the new version of the item as a parameter. If it additionally declares parameters with the special names "origItem" and "changes" those parameters will be provided as well to the remote service.

Parameters

dataManager:RPCDataManager — The data manager.
 
item:Object — The new version of the item.
 
origItem:Object — The original item.
 
changes:Array — list of properties which to change.

Returns
mx.rpc:AsyncToken — AsyncToken reference to the token that will identify this operation in a result or fault event dispatched from this service.