Sun Microsystems iPlanet Integration Server 3.0, Руководство по системе управления

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What Is an iIS Process Engine?
28 iPlanet Integration Server • Process System Guide • August 2001
Once a process definition has been registered with the engine, an iIS process client
application (or an application proxy—see
Figure 1-1 on page 30 ) can open a session
with the engine and create an instance of the process. The client application or
proxy provides any data required to start the process instance, and then the engine
takes over. It assigns activities directly to engine sessions or to queues where they
can be accessed. Client applications—or applications interacting with the engine
through proxies—perform the work required of each activity using whatever
application services, enterprise data, or desktop applications necessary, and then
notify the engine that the activity has been completed. For information on client
applications, see the iIS Process Client Programming Guide. For information about
proxies, see the iIS Backbone System Guide.
The relationship of the engine to iIS process client applications, on the one hand,
and to the process development workshops, on the other, is illustrated in
Figure 1-1 on page 30 . Client applications maintain sessions with an iIS process
engine to initiate a business process or perform its activities in it. The engine can
service a very large number of sessions and manage many instances of many
different process definitions. As process definitions (as well as assignment rule
dictionaries, user profiles, and a validation) are created or modified in the iIS
development environment, they can be registered with the engine, and become the
basis for further process execution.
The engine is thus central to an iIS system, implementing business processes that
require the performance of many activities by many resources.