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Optimize with a SATA RAID Storage Solution
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There are a number of existing naming services, a few of which I'll describe below. They each follow the pattern above, but differ in the details.
As I mentioned earlier, the primary function of a naming system is to bind names to objects (or, in some cases, to references to objects -- more on which in a moment). In order to be a naming service, a service must at the very least provide the ability to bind names to objects and to look up objects by name.
Many naming systems don't store objects directly. Instead, they store references to objects. As an illustration, consider DNS. The address 207.69.175.36 is a reference to a computer's location on the Internet, not the computer itself.
JNDI provides an interface that supports all this common functionality. I will present this interface later in this article.
It's also important to understand how existing naming services differ, since JNDI must provide a workable abstraction that gets around those differences.
Aside from functional differences, the most noticeable difference is the way each naming service requires names to be specified -- its naming convention. A few examples should illustrate the problem.
In DNS, names are built from components that are separated by dots ("."). They read from right to left. The name "www.etcee.com" names a machine called "www" in the "etcee.com" domain. Likewise, the name "etcee.com" names the domain "etcee" in the top-level domain "com."
In LDAP, the situation is slightly more complicated. Names are built from components that are separated by commas (","). Like DNS names, they read from right to left. However, components in an LDAP name must be specified as name/value pairs. The name "cn=Todd Sundsted, o=ComFrame, c=US" names the person "cn=Todd Sundsted" in the organization "o=ComFrame, c=US." Likewise, the name "o=ComFrame, c=US" names the organization "o=ComFrame" in the country "c=US."
As the examples above illustrate, a naming service's naming convention alone has the potential to introduce a significant amount of the flavor of the underlying naming service into JNDI. This is not a feature an implementation-independent interface should have.