Queue Manager Manual

Application Development Steps
Developing Queue Manager Applications
46517 Tandem Computers Incorporated 3–7
Table 3-1. Queue Manager UOW Flow Example
Application Code Queue Manager Action
Inventory Control issues 2 WAITQs to Wait Mgr:
“Alert me when a sales order arrives from
Sales”
“Alert me when a purchase order #
arrives from Purchasing”
Wait Manager performs a read to ensure no entry
on Queue, then waits for sales order and for
purchase order #.
Purchasing issues WAITQ to Wait Manager:
“Alert me when a purchase order
arrives from Inventory Control”
Wait Manager performs a read to ensure no entry
on Queue, then waits for Purchase Order.
Sales issues an ENQ to Entry Manager:
“Enqueue this sales order for Inventory
Control”
Entry Manager enqueues entry on the Queue file
and tells Wait Manager about sales UOW.
Wait Manager acknowledges Entry Mgr, triggers
Inventory Control.
Inventory Control issues DEQ to Entry Manager:
“Dequeue the sales order from Sales”
processes sales order,
issues an ENQ to Entry Manager:
“Enqueue this purchase order for
Purchasing”
Entry Manager dequeues the entry and forwards it
to Inventory Control.
Entry Manager enqueues entry on the Queue and
tells Wait Manager about the purchase order.
Wait Manager acknowledges Entry Manager,
triggers Purchasing.
Purchasing issues DEQ to Entry Manager:
“Dequeue the purchase order from Inventory
Control”
processes the purchase order and issues an
ENQ to Entry Manager:
“Enqueue this purchase order # for Inventory
Control”
Entry Manager dequeues the entry and forwards it
to Purchasing
Entry Manager enqueues the entry on the
Queue File and tells Wait Manager about
the purchase order #.
Wait Manager acknowledges Entry Mgr, triggers
Inventory Control
Inventory Control issues DEQ to Entry Manager:
“Dequeue the purchase order # from
Purchasing”
Entry Manager dequeues the entry and forwards it
to Inventory Control.