The POA (Cont)
  • At initialization, the ORB the creates a single POA
    • available via orb->resolve_initial_references( "RootPOA" )
  • One can use the root POA directly but normally child POAs are created
    • This can be done recursively forming a tree of adapters
  • POAmanagers allow for control of requests
    • Manager states are: holding, active, discarding, inactive
    • Used mostly to control when the server is ready
    • Also useful for activation of POAs
  • Behaviour of POA instances is controlled by policies
    • Policies are assigned to POAs only at creation
    • Seven standard policies are defined:
      • threading, lifespan, object ID assignment, object ID uniqueness
      • servant retention, request processing, implicit activation
    • Each policy has two or three possible values, one of which is the default.

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