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Client-side Policy management is performed through operations accessible in the following contexts:
• ORB-level Policies - A locality-constrained PolicyManager is accessible through the ORB interface. This PolicyManager has operations through which a set of Policies can be applied and the current overriding Policy settings can be obtained. Policies applied at the ORB level override any system defaults. The ORB’s PolicyManager is obtained through an invocation of ORB::resolve_initial_references, specifying an identifier of “ORBPolicyManager.?
• Thread-level Policies -A standard PolicyCurrent is defined with operations for the querying and applying of quality of service values specific to a thread. Policies applied at the thread level override any system defaults or values set at the ORB level. The locality-constrained PolicyCurrent is obtained through an invocation of ORB::resolve_initial_references, specifying an identifier of “PolicyCurrent.? When accessed from a newly spawned thread, the PolicyCurrent initially has no overridden policies. The PolicyCurrent also has no overridden values when a POA with ThreadPolicy of ORB_CONTROL_MODEL dispatches an invocation to a servant. Each time an invocation is dispatched through a SINGLE_THREAD_MODEL POA, the thread-level overrides are reset to have no overridden values.
• Object-level Policies - Operations are defined on the base Object interface through which a set of Policies can be applied. Policies applied at the Object level override any system defaults or values set at the ORB or Thread levels. In addition, accessors are defined for querying the current overriding Policies set at the Object level, and for obtaining the current effective client-side Policy of a given PolicyType. The effective client-side Policy is the value of a PolicyType that would be in effect if a request were made. This is determined by checking for overrides at the Object level, then at the Thread level, and finally at the ORB level. If no overriding policies are set at any level, the system-dependent default value is returned. Portable applications are expected to override the ORB-level policies since default values are not specified in most cases.