FTGroupMonitor

Constructor

Visual Basic

Overloads Public Sub New(
    ByVal queue As Queue,
    ByVal groupStateChangedEventHandler
            As GroupStateChangedEventHandler,
    ByVal transport As Transport,
    ByVal groupName As String,
    ByVal lostInterval As Double,
    ByVal closure As Object )
Overloads Public Sub New(
    ByVal queue As Queue,
    ByVal transport As Transport,
    ByVal groupName As String,
    ByVal lostInterval As Double,
    ByVal closure As Object )

C#

public FTGroupMonitor(
    Queue queue,
    GroupStateChangedEventHandler
      groupStateChangedEventHandler,
    Transport transport,
    string groupName,
    double lostInterval,
    object closure )
public FTGroupMonitor(
    Queue queue,
    Transport transport,
    string groupName,
    double lostInterval,
    object closure )

Purpose

Monitor a fault tolerance group.

Remarks

The monitor event handler delegate receives the number of active members as an argument.

The group need not have any members at the time of this constructor call.


Parameter	Description
`queue`	Place events for this monitor on this event queue.
`groupStateChangedEventHandler`	On dispatch, process the event with this delegate. Every group monitor requires a handler delegate. For convenience, supply the delegate to the constructor through this parameter. (It also possible to omit this parameter, and add the handler to the GroupStateChanged event later, using a .NET call.)
`transport`	Listen on this transport for fault tolerance internal protocol messages (such as heartbeat messages).
`groupName`	Monitor the fault tolerant group with this name. The group name must conform to the syntax required for Rendezvous subject names. For details, see Subject Names in TIBCO Rendezvous Concepts. See also, Group Name.
`lostInterval`	When the heartbeat signal from an active member has been silent for this interval (in seconds), Rendezvous fault tolerance software considers that member lost, and queues a monitor event. The interval must be positive. To determine the correct value, see Step 4: Choose the Intervals in TIBCO Rendezvous Concepts. See also, Lost Interval.
`closure`	Store this closure data in the monitor object.

Lost Interval

The monitor uses the lostInterval to determine whether a member is still active. When the heartbeat signal from an active member has been silent for this interval (in seconds), the monitor considers that member lost, and queues a monitor event.

We recommend setting the lostInterval identical to the group’s activationInterval, so the monitor accurately reflects the behavior of the group members.

Group Name

The group name must be a legal Rendezvous subject name (see Subject Names in TIBCO Rendezvous Concepts in TIBCO Rendezvous Concepts). You may use names with several elements; for examples, see Multiple Groups in TIBCO Rendezvous Concepts.