Java Distributed Computing

Naming Service

The Naming Service is arguably the most commonly used service in the CORBA family. We used the Naming Service in our CORBA example in Chapter 3 to look up our CORBA-based Solver object. The Naming Service provides a means for objects to be referenced by name within a given naming context. A naming context is a scoping mechanism for names, similar in philosophy to class packages in Java. Within a particular context, names must be unique, and contexts can be nested to form compound contexts and names. Figure 2.1 shows two naming contexts in the form of Venne diagrams: one, whose topmost context is named “BankServices,” defines names for objects in a banking application; the other, named “LANResources,” defines names for network resources such as printers, compute servers, data servers, etc. The “BankServices” naming context contains a single object named “AuthorizationAgent,” and a subcontext named “CorporateAccount.” The “LANServices” context contains a “DataServer” context and a “Printer” context, and each of these contains two named objects.

Figure B-1. Sample naming contexts

Agents in a distributed system can add named objects to the Naming Service by binding objects to a particular name within a context. Other agents can then look up these objects by resolving their names into object references. The name of an object is made up of a sequence of name components ...