Using javax.naming.spi.DirObjectFactory to lookup objects from an LDAP

Question

I've implemented an object factory to lookup LDAP objects, but the supplied context does not return the DN (via nameCtx.getNameInNamespace()) from the LDAP. Am i doing it wrong in some way?

public class LdapPersonFactory implements DirObjectFactory {
        @Override
        public Object getObjectInstance(Object obj, Name name, Context nameCtx,
          Hashtable<?, ?> environment, Attributes attrs) throws Exception {
         if (attrs == null)
          return null;
         Attribute oc = attrs.get("objectclass");
         if (oc != null && oc.contains("inetOrgPerson")) {
          String surname = (String) attrs.get("sn").get();
          String givenName = (String) attrs.get("givenname").get();
          String dn = nameCtx.getNameInNamespace();
          return new LdapPerson(dn, givenName, surname);
         }
         return null;
        }
    }

nameCtx.getNameInNamespace() only returns an empty string.

Answer 1

Maybe?

String dn = (String) attrs.get("dn").get();

It should be an attribute like any other?

Answer 2

String dn = (String) attrs.get("dn").get();

this throws a NamingException only.
I don't think that the distinguished name (DN) is an attribute of the LDAP object, it's more like an identity key in the LDAP-world.

Answer 3

It could be that your context points to the "root node" or what ever it is called. That is, the node that has the top-level namespaces as its children.

I suppose it could also be that the context isn't bound at the time you call getNameInNamespace, although I would expect that to throw an exception.

I use spring-ldap for this sort of stuff, and have not experienced a similar bug with its DirContextAdapter and LdapTemplate classes. But then again, I always bind them to a specific namespace.