|
|
Contents |
A fundamental facility in any computing system is the naming service--the means by which names are associated with objects, and by which objects are found given their names. In using almost any computer program or system, you are always naming one object or another. When you use an electronic mail system, for example, you must provide the name of the recipient to whom you want to send mail. When you want to access a file in the computer, you must supply its name.Many naming services are extended with a directory service. While a naming service allows you to look up an object given its name, a directory service also allows such objects to have attributes. Therefore, in addition to lookup, you can also get an object's attributes or search for objects given their attributes.
You might be familiar with the telephone company's directory service. A computer's directory service is very much like a telephone company's directory service in that both can be used to store information such as telephone numbers and addresses. In addition, the computer's directory service is much more powerful in that it is available online and can be used to store a variety of information, for consumption by users, programs, and even computer systems themselves.
The rest of this lesson explains these concepts in more detail and provides definitions for terms commonly used when talking about naming and directory services. It also discusses how Java programs can make use of naming and directory services. A summary of the terms is provided at the end of the lesson in the form of a glossary.
|
|
Contents |