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Web services take float with JAXR

Use JAXR to find and register Web services

By Frank Sommers, JavaWorld.com, 05/17/02

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The job of cataloguing the world's species is straightforward, methodical, and slow. Taxonomists...add an average of 13,000 species a year to the list of known organisms. At that rate it would take centuries to complete the census. Because no central storehouse coordinates the results, even the number of species named so far—between 1.5 million and 1.8 million—is uncertain.
(Laura Tangley, "How Many Species Are There?" US News and World Report, August 1997)


How do you find what you are looking for? At home, you might organize things any way you like, provided you find what you need quickly. If you share your dwellings with others, you must all be able to find the things you mutually need. Of course, you can still organize your own desk in any manner, including—if you're like me—completely unorganized.

At your office, more people rely on the ability to locate commonly needed forms and other supplies with minimum effort. Administrative assistants label file cabinets and drawers with the names of their contents so other people can easily locate what they need. Even if you dislike that organization method, you would not rearrange those cabinets without first asking your colleagues. Since everyone depends on the ability to find needed office items, the desire for a shared organizational structure takes precedence over personal convenience.

The way we organize our computer files mirrors the office file cabinet example. When looking for the minutes from a year-old client meeting, you'd first find the folder with the client's name, look for the Meetings subfolder, and then perhaps sort that folder's contents by date. Of course, another person might organize it differently: he might have a Work folder, then a Meetings folder, inside which he would group items by client. That difference can be problematic when you're on vacation and your coworker urgently needs that meeting note. Thus, for important files, offices typically allocate shared directories, or network drives, and create policies on where and how you should save files.

The moral here is that we tend to name things and then categorize them, assigning each category a name, in turn. That hierarchical approach has served us for many a millennium in grasping what we know of the universe. Assigning names is how things enter our conceptual world, and that naming ability lets us have language. Indeed, "spoken words are the symbols of mental experience, and written words are the symbols of spoken words." (See Aristotle.) As we discover relationships between things, we categorize them according to those relationships. That categorization is a mental experience, and the symbol for that experience is the category name. A categorization system based on names is a taxonomy.

Web service registries

While file systems rely on naming and categorization for organizing files, naming and directory services extend that concept to the network. A directory suggests it contains a complete inventory of computing resources in the realm of things it categorizes. Just as a telephone directory aims to comprehensively include all lawyers, accountants, or art historians living in a city, a naming and directory service's usefulness is greatly affected by whether it contains all the printers, database servers, users, or administrators in an organization or department (domain). When a user wishes to log into a database, for example, that database might contact a directory server to determine the user's access privileges. If a directory contained only a partial list of authorized users, its usefulness to the organization would be questionable.

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