JNDI !! What the heck is it ? Part 2 'Directory services'

If you understood the first part of the series , this should be cake walk. We will talk about Directory services in this part. So lets start.

To understand directory services, think of any travel website where you can book a flight based on various parameters like price, timing, etc. E.g. London to Tokyo flight in 1000$ at 11pm on wednesday.
Directory services are similar to naming services where you can associate resources with names and you can get the objects by their names. However directory services are very similar to how these travel websites work as well. We can search an entity or resource based on their different attributes. Most commonly directory services allow us to store objects hierarchically.

So if we think directory services are nothing but a database like systems where we can query required objects based on our own criteria by specifying a criteria filter. These filters allow us to configure different parameters like 'depth of tree nodes' etc.

Following diagram represents the concept of directory services that we just talked about.

The most common protocol for accessing the directory service is LDAP (lightweight directory access protocol) LDAP defines how client applications can access or manipulate the data on the directory servers. As mentioned above, LDAP provides APIs to search the directory servers based on filters and parameters.

This is pretty much it as far as concept of directory services goes. In next section we will talk about the real thing; the JNDI

See you then :)