Service Objects
  • IDL may be used to define interfaces which are more like APIs (services) than objects
    • Such objects are usually singletons, so memory usage per Servant is not relevant
      • Similar to the factories in the Auction Server.
    • And usually the objects are transient, no need for the reference to persist
      • Unless clients want to hold on to the reference
    • There is no need for most of the POA's features
      • Request processing: USE_ACTIVE_OBJECT_MAP_ONLY
      • Servant retention: RETAIN
      • Lifespan: TRANSIENT
      • (in fact, this matches the rootPOA policies)
    • At start up, code would create the POA and add the single instance to it
    • Creation of BidFactory is an example of such a singleton

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