CMMessage

Class

Superclasses

System.Object
  Message
    CMMessage

Visual Basic

Public Class CMMessage
  Inherits Message

C#

public class CMMessage : Message

Purpose

Represent labeled messages.

Method	Description	Page
Message Life Cycle and Properties
CMMessage	Create a CM message object.	CMMessage

Member	Description
Public Instance Properties
FieldCount	uint The number of fields in the message. (Inherited from Message.) This count includes only the immediate fields of the message; it does not include fields within recursive submessages.	Get
ReplySubject	string The reply subject of the message. (Inherited from Message.) For more information, see Subjects.	Get Set
Sender	string The correspondent name of the sender transport that sent the certified message.	Get
SendSubject	string The destination subject of the message. (Inherited from Message.) When this property is null, the message is unsendable. For more information, see Subjects.	Get Set
SequenceNumber	ulong The sequence number of the certified message. For details, see Sequence Number.	Get
Size	uint The size of the message (in bytes). (Inherited from Message.)	Get
TimeLimit	double The message time limit of the certified message. For details, see Sequence Number.	Get Set

Inherited Methods
Message.AddField Message.Expand Message.GetField Message.GetFieldByIndex Message.GetFieldInstance Message.RegisterCustomDataType Message.RemoveField Message.RemoveFieldInstance Message.Reset Message.ToByteArray Message.UpdateField

Sequence Number

Rendezvous certified delivery sending methods automatically generate positive sequence numbers for outbound labeled messages.

In receiving programs, the sequence number property indicates whether an inbound message is certified:

•

If the message is from a CM sender, and the CM listener is registered for certified delivery with that sender, then the SequenceNumber property is a valid sequence number.

•

If the message is from a CM sender, but the listener is not registered for certified delivery, then attempting to get the SequenceNumber property throws an exception with the status code NotFound.

Notice that the first labeled message that a program receives on a subject might not be certified; that is, the sender has not registered a certified delivery agreement with the listener. If appropriate, the certified delivery library automatically requests that the sender register the listener for certified delivery. (See Discovery and Registration for Certified Delivery in TIBCO Rendezvous Concepts.)

An uncertified CM message can also result when the sender explicitly disallows or removes the listener.

Note

Release 5 Interaction In release 6 (and later) the sequence number is a 64-bit unsigned integer, while in older releases (5 and earlier) it is a 32-bit unsigned integer. When 32-bit senders overflow the sequence number, behavior is undefined. When 64-bit senders send sequence numbers greater than 32 bits, 32-bit receivers detect malformed label information, and process the message as an ordinary reliable message (uncertified and unlabeled).

Time Limit

Every labeled message has a time limit, after which the sender no longer certifies delivery. Time limits represent the minimum time that certified delivery is in effect.

Outbound Messages Sending programs can explicitly set the message time limit property (before sending a CM message). If the time limit property is not already set for the outbound message, CMTransport.Send sets it to the transport’s default time limit (see DefaultTimeLimit); if that default is not set for the transport, the default time limit is zero (no time limit). Time limit values must be non-negative, and represent a whole number seconds. It is meaningful to set this property only on outbound messages.

Inbound Messages Zero is a special value, indicating no time limit. This value represents the total time limit of the message, not the time remaining.

See Also

Message

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