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22.2.6.1 typedef short Ordering
Describes the ordering policy for the consideration of routers that prioritize delivery of requests. Values of type Ordering
are used in conjunction with a QueueOrderPolicy
as described in “interface QueueOrderPolicy? on page 22-12. This policy is only used
if the effective RoutingType is at least ROUTE_FORWARD (which implies the use of a Router). Support for multiple ordering
policies is indicated by “or?-ing together individual values in a combined Ordering.
• ORDER_ANY - the client doesn't care in what order its requests are processed.
• ORDER_TEMPORAL - the client wants to be sure that its requests are processed in the order in which they were issued. ORDER_TEMPORAL is the default.
• ORDER_PRIORITY -the client wants its requests processed based on the priority assigned in the QoS structure described below.
• ORDER_DEADLINE - the client wants its requests ordered so that those whose time_to_live is about to expire are moved to the front of the queue.
22.2.6.2 interface QueueOrderPolicy
This interface is a local object derived from CORBA::Policy. It is used to indicate the basis upon which a Router orders delivery
of requests. When instances of QueueOrderPolicy are created, a value of type Messaging::Ordering is passed to CORBA::ORB::create_policy.
This specified Ordering value can be the result of “or?-ing together individual orderings. An instance of QueueOrderPolicy
may be specified when creating a POA (and therefore may be represented in Object references). In addition, an Object reference’s
QueueOrderPolicy may be overridden by the client. If set on both the client and server, reconciliation is performed by intersecting
the server-specified list of supported Ordering values with the list of values in the client’s effective override. When an
instance of QueueOrderPolicy is propagated within a PolicyValue in a TAG_POLICIES Profile Component or INVOCATION_POLICIES
Service Context, the ptype has value QUEUE_ORDER_POLICY_TYPE and the pvalue is a CDR encapsulation containing a Messaging::Ordering.