Clients (Client State Objects)

When a client initially establishes a connection with a Broker, the Broker generates a client state object for that client.

The client state object maintains the following information about the client:

Client ID. An ID that uniquely identifies the client.

Application Name. An optional label that client programs can use to identify the system or application to which they belong.

Client Group. The name of the client group to which the client belongs.

Subscription List. The list of document types this client wants to receive.

Queue. The list of document instances that are currently enqueued for the client.

Sessions. A client can optionally enable "shared-state" when it connects to a Broker. The shared-state property enables multiple clients to connect to the Broker using the same client state object. (Typically, a client application does this to enable multiple client processes to retrieve and process documents from the client's queue, thereby improving performance.) When shared state is enabled, the client state object contains a list of sessions. Each session identifies the IP address of a client that is currently connected to the Broker using that client state object. For example a trigger on a cluster of two Integration Servers appears as one client on the Broker (that is, they share the same client state object), but the client state object has two sessions, one for each Integration Server.

When a client disconnects from Broker, the disposition of its client state object is determined by the lifecycle property in the client group to which the client belongs.

If the lifecycle value is...	The Broker...
Explicit Destroy	Maintains the client state object after the client disconnects. The client state object continues to receive documents in its queue, even though the client program is not actively connected to the Broker. The client can subsequently reconnect (using the same client ID) and retrieve documents from the queue.
Destroy on Disconnect	Drops the client state object. When the client state object is dropped, the Broker loses all knowledge of that client.

You use the Broker user interface to examine the client state objects that represent the clients that are using the Broker. You can also use the Broker user interface to forcibly disconnect a client from a Broker and to instantiate a test client for diagnostic purposes.

For information about monitoring and managing Broker clients, see Managing Clients.