| 摘要 |
Remote procedure call (RPC) objects are provided in both a client node and a server node of a client-server network for invoking and responding to service requests generated by calls to local service objects. Specifically, the RPC objects comprise a "caller" object which, once instantiated, accepts service requests from client objects. A service request made by calling a function in the local service object is automatically routed by the caller object to a local service program if the requests can be serviced locally, or to a remote server node if the appropriate service program is located on the remote node. The RPC objects also include a "dispatcher" object which is located at the remote service node and receives incoming service requests. The service requests are actually satisfied by means of service functions which are part of service objects in the server node, but these latter service functions are associated with the local service objects by means of a "dictionary" located in the dispatcher object. In some cases, a service located at a remote node may itself need data or functions which, in turn, reside at other nodes. In this case, the dispatcher object is provided with additional "sub-objects" or "child" objects which include their own dispatcher objects. In this manner, incoming requests directed to the "parent" dispatcher object are forwarded to the child dispatcher objects for service.
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