Java Enterprise in a Nutshell, Third Edition

Creating Directory Entries

So far, we have been accessing directory entries that are already present in the directory. Now it’s time to learn how to create directory entries of our own, using the createSubcontext() method of DirContext. As we discussed earlier, when you create a subcontext of a Context object, the service provider controls the type of object that is created. With a DirContext, this is not the case; you actually have complete control over the type of object you create with createSubcontext() (within the constraints of the directory schema, of course).

As noted earlier, the object class definition determines the type of a directory entry, and the entry stores its object class as an attribute. So, in order to create a directory entry, we must pass the object class attribute and some other attributes into the parent entry’s createSubcontext() method.

Most directories require that you specify attributes for at least the object class definition (e.g., "objectclass=") and key attribute (e.g., common name, "cn=") of a directory entry. Often directories require that you specify more attributes than just these. The minimum set of attributes necessary for creating a directory entry is called the mandatory attributes. They are mandatory because, if you don’t specify them, createSubcontext() throws an InvalidAttributesException. Other attributes that aren’t required, but that add more useful data to the entry, are called extended attributes.

Say we have a reference to a