Microsoft AD, JNDI and LDAP

Question

Hello,
I working to move an application off of Novell eDirectory onto Microsoft AD. The program successfully binds to AD, the search filter executes correctly and the attributes are returned as expected. However, the final call to searchResults.hasMore() is not returning! In other words, the final call, which should return false, is not returning at all.
Any ideas?
-Bryan
try
hashtable = null;
hashtable = new Hashtable();
hashtable.put("java.naming.ldap.version", "3");
hashtable.put Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
hashtable.put(Context.SECURITY_AUTHENTICATION, "Simple");
hashtable.put(Context.REFERRAL, "follow");
hashtable.put(Context.PROVIDER_URL, url);
hashtable.put(Context.SECURITY_PRINCIPAL, loginDN);
hashtable.put(Context.SECURITY_CREDENTIALS, passwd);
ctx = new InitialLdapContext(hashtable, null);
SearchControls sc = new SearchControls();
sc.setSearchScope(SearchControls.SUBTREE_SCOPE);
sc.setReturningAttributes(new String[] {"mailNickname", "givenName", "sn", "mail"});
NamingEnumeration results = ctx.search(base, filter, sc);
cns = new ArrayList(25);
givenNames = new ArrayList(25);
mails = new ArrayList(25);
surNames = new ArrayList(25);
while (results.hasMore()) // hangup occurring here when hasMore() should return false
SearchResult sr = (SearchResult)results.next();
Attributes attrs = sr.getAttributes();
Enumeration enum = attrs.getAll();
while (enum.hasMoreElements())
System.out.println(enum.nextElement());
cns.add((String)(attrs.get("mailNickname").get()));
givenNames.add((String)(attrs.get("givenName").get()));
surNames.add((String)(attrs.get("sn").get()));
mails.add((String)(attrs.get("mail").get()));
finally
try {ctx.close();}
catch (Exception e) {}
}

Answer 1

I'll take a bit of a stab at this, although your code sample seems to have some typos, missing a few braces and few catches.
Anyway, there are some subtle differences between the behaviour of AD and other LDAP directories. One is that by default AD limits the number of objects that can be returned in a LDAP query to 1000. I think I described this in the post JNDI, Active Directory, Paging and Range Retrieval available at http://forum.java.sun.com/thread.jspa?threadID=578347&tstart=0
Also there are differences in the behaviour of Enumeration.hasMore & Enumeration.hasMoreElements, Enumeration.hasMore throws exception s and will not return false, whereas hasMoreElements does not throw an exception and will return false. Have a look at http://java.sun.com/j2se/1.3/docs/api/javax/naming/NamingEnumeration.html
So I'll assume that AD is causing an exception to be thrown, perhaps a SizeLimitExceededException or PartialResultsException.
Either process the exception, or use hasMoreElements instead.