(Adobe® Flex™ Data Services 2 only)
Packagemx.messaging
Classpublic class MessageAgent
InheritanceMessageAgent Inheritance EventDispatcher Inheritance Object
ImplementsIMXMLObject
SubclassesConsumer, Producer

The MessageAgent class provides the basic low-level functionality common to message handling for a destination.

Note: For advanced use only. Use this class for creating custom message agents like the existing Producer and Consumer classes.

MXML Syntaxexpanded Hide MXML Syntax

All message agent classes, including the Producer and Consumer classes, extend MessageAgent and inherit the following tag attributes:

   <mx:tagname
Properties channelSet="No default." clientId="No default." connected="false" destination="No default." requestTimeout="-1" subtopic="No default." Events acknowledge="No default." channelConnect="No default." channelDisconnect="No default." channelFault="No default." fault="No default." propertyChange="No default." />


Public Properties
 PropertyDefined by
  channelSet : ChannelSet
Provides access to the ChannelSet used by the MessageAgent.
MessageAgent
  clientId : String
[read-only] Provides access to the client id for the MessageAgent.
MessageAgent
  connected : Boolean
[read-only] Indicates whether this MessageAgent is currently connected to its destination via its ChannelSet.
MessageAgent
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  destination : String
Provides access to the destination for the MessageAgent.
MessageAgent
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  requestTimeout : int
Provides access to the request timeout in seconds for sent messages.
MessageAgent
  subtopic : String
Provides access to the subtopic for the remote destination that the MessageAgent uses.
MessageAgent
Public Methods
 MethodDefined by
  
Constructor.
MessageAgent
  
Invoked by a MessageResponder upon receiving a result for a sent message.
MessageAgent
 Inherited
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.
EventDispatcher
  
Handles a CONNECT ChannelEvent.
MessageAgent
  
Handles a DISCONNECT ChannelEvent.
MessageAgent
  
Handles a ChannelFaultEvent.
MessageAgent
  
Disconnects the MessageAgent's network connection.
MessageAgent
 Inherited
Dispatches an event into the event flow.
EventDispatcher
  
Invoked by a MessageResponder upon receiving a fault for a sent message.
MessageAgent
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
  
initialized(document:Object, id:String):void
Called after the implementing object has been created and all properties specified on the tag have been assigned.
MessageAgent
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
  
Logs the MessageAgent out from its remote destination.
MessageAgent
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
  
setCredentials(username:String, password:String):void
Sets the credentials that the MessageAgent uses to authenticate to destinations.
MessageAgent
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
  
setRemoteCredentials(username:String, password:String):void
Sets the remote credentials that will be passed through to the remote destination for authenticating to secondary systems.
MessageAgent
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Protected Methods
 MethodDefined by
  
Used to automatically initialize the channelSet property for the MessageAgent before it connects for the first time.
MessageAgent
  
Sends a Message from the MessageAgent to its destination using the agent's ChannelSet.
MessageAgent
Events
 EventSummaryDefined by
   Dispatched when an acknowledge message is received for a sent message.MessageAgent
   Dispatched when the underlying Channel the MessageAgent is using connects.MessageAgent
   Dispatched when the underlying Channel the MessageAgent is using disconnects.MessageAgent
   Dispatched when the underlying Channel the MessageAgent is using faults.MessageAgent
   Dispatched when a message fault occurs.MessageAgent
   Dispatched when the connected property of the MessageAgent changes.MessageAgent
Property detail
channelSetproperty
channelSet:ChannelSet  [read-write]

Provides access to the ChannelSet used by the MessageAgent. The ChannelSet can be manually constructed and assigned, or it will be dynamically initialized to use the configured Channels for the destination for this MessageAgent.

Implementation
    public function get channelSet():ChannelSet
    public function set channelSet(value:ChannelSet):void
clientIdproperty 
clientId:String  [read-only]

Provides access to the client id for the MessageAgent. Agents are assigned their client id by the remote destination.

Implementation
    public function get clientId():String
connectedproperty 
connected:Boolean  [read-only]

Indicates whether this MessageAgent is currently connected to its destination via its ChannelSet. The propertyChange event is dispatched when this property changes.

This property can be used as the source for data binding.

Implementation
    public function get connected():Boolean
destinationproperty 
destination:String  [read-write]

Provides access to the destination for the MessageAgent. Changing the destination will disconnect the MessageAgent if it is currently connected.

This property can be used as the source for data binding.

Implementation
    public function get destination():String
    public function set destination(value:String):void

Throws
InvalidDestinationError — If the destination is null or zero-length.
requestTimeoutproperty 
requestTimeout:int  [read-write]

Provides access to the request timeout in seconds for sent messages. If an acknowledgement, response or fault is not received from the remote destination before the timeout is reached the message is faulted. A value less than or equal to zero prevents request timeout.

Implementation
    public function get requestTimeout():int
    public function set requestTimeout(value:int):void
subtopicproperty 
subtopic:String  [read-write]

Provides access to the subtopic for the remote destination that the MessageAgent uses.

This property can be used as the source for data binding.

Implementation
    public function get subtopic():String
    public function set subtopic(value:String):void
Constructor detail
MessageAgent()constructor
public function MessageAgent()

Constructor.

Method detail
acknowledge()method
public function acknowledge(ackMsg:AcknowledgeMessage, msg:IMessage):void

Invoked by a MessageResponder upon receiving a result for a sent message. Subclasses may override this method if they need to perform custom acknowledgement processing, but must invoke super.acknowledge() as well. This method dispatches a MessageAckEvent.

Parameters
ackMsg:AcknowledgeMessage — The AcknowledgMessage returned.
 
msg:IMessage — The original sent message.
channelConnectHandler()method 
public function channelConnectHandler(event:ChannelEvent):void

Handles a CONNECT ChannelEvent. Subclasses that need to perform custom processing should override this method, and invoke super.channelConnectHandler().

Parameters
event:ChannelEvent — The ChannelEvent.
channelDisconnectHandler()method 
public function channelDisconnectHandler(event:ChannelEvent):void

Handles a DISCONNECT ChannelEvent. Subclasses that need to perform custom processing should override this method, and invoke super.channelDisconnectHandler().

Parameters
event:ChannelEvent — The ChannelEvent.
channelFaultHandler()method 
public function channelFaultHandler(event:ChannelFaultEvent):void

Handles a ChannelFaultEvent. Subclasses that need to perform custom processing should override this method, and invoke super.channelFaultHandler().

Parameters
event:ChannelFaultEvent — ChannelFaultEvent
disconnect()method 
public function disconnect():void

Disconnects the MessageAgent's network connection. This method does not wait for outstanding network operations to complete.

fault()method 
public function fault(errMsg:ErrorMessage, msg:IMessage):void

Invoked by a MessageResponder upon receiving a fault for a sent message. Subclasses may override this method if they need to perform custom fault processing, but must invoke super.fault() as well. This method dispatchs a MessageFaultEvent.

Parameters
errMsg:ErrorMessage — The ErrorMessage.
 
msg:IMessage — The original sent message that caused this fault.
initChannelSet()method 
protected function initChannelSet(message:IMessage):void

Used to automatically initialize the channelSet property for the MessageAgent before it connects for the first time. Subtypes may override to perform custom initialization.

Parameters
message:IMessage — The message that needs to be sent.
initialized()method 
public function initialized(document:Object, id:String):void

Called after the implementing object has been created and all properties specified on the tag have been assigned.

Parameters
document:Object — MXML document that created this object.
 
id:String — id used by the document to refer to this object. If the object is a deep property on the document, id is null.
internalSend()method 
protected final function internalSend(message:IMessage):void

Sends a Message from the MessageAgent to its destination using the agent's ChannelSet. MessageAgent subclasses must use this method to send their messages.

Parameters
message:IMessage — The message to send.

Throws
InvalidDestinationError — If no destination is set.
logout()method 
public function logout():void

Logs the MessageAgent out from its remote destination. Logging out of a destination applies to everything connected using the same ChannelSet as specified in the server configuration. For example, if several DataService components are connected over an RTMP channel and logout() is invoked on one of them, all other client components that are connected using the same ChannelSet are also logged out.

setCredentials()method 
public function setCredentials(username:String, password:String):void

Sets the credentials that the MessageAgent uses to authenticate to destinations. The credentials are applied to all services connected over the same ChannelSet.

Parameters
username:String — The username.
 
password:String — The password.
setRemoteCredentials()method 
public function setRemoteCredentials(username:String, password:String):void

Sets the remote credentials that will be passed through to the remote destination for authenticating to secondary systems.

Parameters
username:String — The username.
 
password:String — The password.
Event detail
acknowledgeevent 
Event object type: mx.messaging.events.MessageAckEvent
MessageAckEvent.type property = mx.messaging.events.MessageAckEvent.ACKNOWLEDGE

Dispatched when an acknowledge message is received for a sent message.

The ACKNOWLEDGE event type; dispatched upon receipt of an acknowledgement.

The value of this constant is "acknowledge".

The properties of the event object have the following values:

PropertyValue
acknowledgeMessage Utility property to get the message property from MessageEvent as an AcknowledgeMessage.
bubblesfalse
cancelablefalse
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
correlate The original Message correlated with this acknowledgement.
messageThe Message associated with this event.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.
channelConnectevent  
Event object type: mx.messaging.events.ChannelEvent
ChannelEvent.type property = mx.messaging.events.ChannelEvent.CONNECT

Dispatched when the underlying Channel the MessageAgent is using connects.

The CONNECT event type; indicates that the Channel connected to its endpoint.

The value of this constant is "channelConnect".

The properties of the event object have the following values:

PropertyValue
bubblesfalse
cancelablefalse
channelThe channel that generated this event.
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.
reconnecting Indicates whether the channel that generated this event is reconnecting.
rejected Indicates whether the channel that generated this event was rejected. This would be true in the event that the channel has been disconnected due to inactivity and should not attempt to failover or connect on an alternate channel.
channelDisconnectevent  
Event object type: mx.messaging.events.ChannelEvent
ChannelEvent.type property = mx.messaging.events.ChannelEvent.DISCONNECT

Dispatched when the underlying Channel the MessageAgent is using disconnects.

The DISCONNECT event type; indicates that the Channel disconnected from its endpoint.

The value of this constant is "channelDisconnect".

The properties of the event object have the following values:

PropertyValue
bubblesfalse
cancelablefalse
channelThe channel that generated this event.
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.
reconnecting Indicates whether the channel that generated this event is reconnecting.
rejected Indicates whether the channel that generated this event was rejected. This would be true in the event that the channel has been disconnected due to inactivity and should not attempt to failover or connect on an alternate channel.
channelFaultevent  
Event object type: mx.messaging.events.ChannelFaultEvent
ChannelFaultEvent.type property = mx.messaging.events.ChannelFaultEvent.FAULT

Dispatched when the underlying Channel the MessageAgent is using faults.

The FAULT event type; indicates that the Channel faulted.

The value of this constant is "channelFault".

The properties of the event object have the following values:

PropertyValue
bubblesfalse
cancelablefalse
channelThe Channel that generated this event.
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
faultCodeProvides destination-specific details of the failure.
faultDetailProvides access to the destination-specific reason for the failure.
faultStringProvides access to the underlying reason for the failure if the channel did not raise the failure itself.
reconnecting Indicates whether the channel that generated this event is reconnecting.
rootCause Provides access to the underlying reason for the failure if the channel did not raise the failure itself.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.
faultevent  
Event object type: mx.messaging.events.MessageFaultEvent
MessageFaultEvent.type property = mx.messaging.events.MessageFaultEvent.FAULT

Dispatched when a message fault occurs.

The FAULT event type; dispatched for a message fault.

The value of this constant is "fault".

The properties of the event object have the following values:

PropertyValue
bubblesfalse
cancelablefalse
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
faultCodeProvides destination-specific details of the failure.
faultDetailProvides access to the destination-specific reason for the failure.
faultStringProvides access to the underlying reason for the failure if the channel did not raise the failure itself.
messageThe ErrorMessage for this event.
rootCause Provides access to the underlying reason for the failure, if one exists.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.
propertyChangeevent  
Event object type: mx.events.PropertyChangeEvent
PropertyChangeEvent.type property = mx.events.PropertyChangeEvent.PROPERTY_CHANGE

Dispatched when the connected property of the MessageAgent changes. Also dispatched when the subscribed of a Consumer changes.

The PropertyChangeEvent.PROPERTY_CHANGE constant defines the value of the type property of the event object for a PropertyChange event.

The properties of the event object have the following values:

PropertyValue
bubblesDetermined by the constructor; defaults to false.
cancelableDetermined by the constructor; defaults to false.
kindThe kind of change; PropertyChangeEventKind.UPDATE or PropertyChangeEventKind.DELETE.
oldValueThe original property value.
newValueThe new property value, if any.
propertyThe property that changed
sourceThe object that contains the property that changed.
currentTargetThe Object that defines the event listener that handles the event. For example, if you use myButton.addEventListener() to register an event listener, myButton is the value of the currentTarget.
targetThe Object that dispatched the event; it is not always the Object listening for the event. Use the currentTarget property to always access the Object listening for the event.

See also