parse memberOf attribute to get group in spring security3 - string

Question

I am using spring security 3.1.3 for authentication via LDAP, code is working fine.Now, I want to get group of authenticated user. I've developed my custom LdapAuthoritiesPopulator in my application.Below is my code.
public Collection<? extends GrantedAuthority> getGrantedAuthorities(DirContextOperations userData, String username) {
List<GrantedAuthority> grantedAuthorities = null;
Object[] objects = userData.getObjectAttributes("memberOf");
for(Object object: objects){
System.out.println((String)object + "---------"+object.getClass());
}
}
console output : CN=Administrators,CN=Builtin,DC=example,DC=in
I don't want to perform string parsing, Is there any inbuilt function so that I can get group of authenticated user in my above implementation?

Answer 1

Have you considered using ActiveDirectoryLdapAuthenticationProvider instead of a customized LdapAuthenticationProvider? It's tailor made to deal with AD, e.g. the mapping from group memberships to authorities is already implemented in its loadUserAuthorities() method.
Refer to 19.5. Active Directory Authentication in the reference docs for more details.

Answer 2

Your question is really not clear about what you really want to do. I'm assuming based on whatever has been discussed so far that you want to extract (i.e., parse out) the name of the group from the DN you get. In your example, you want to extract the "CN=Administrators" RDN from "CN=Administrators,CN=Builtin,DC=example,DC=in" ??! Again, this is my assumption based on what I read and I understood (sort of).
If you don't want to do the parsing, you can perhaps use JNDI's CompoundnName class with your own syntax definition, but I'm not sure if using this class will give you any dramatic advantage over your own string parsing, which actually should not be complicated. But, here's how you can use CompoundName:
import java.util.Properties;
import javax.naming.CompoundName;
public class NameTestSimple {
public static void main(String[] args) throws Exception{
Properties syntax = new Properties();
syntax.setProperty("jndi.syntax.direction", "left_to_right");
syntax.setProperty("jndi.syntax.separator", ",");
syntax.setProperty("jndi.syntax.ignorecase", "true");
syntax.setProperty("jndi.syntax.escape", "\\");
syntax.setProperty("jndi.syntax.trimblanks", "true");
// syntax.setProperty("jndi.syntax.separator.ava", ",");
syntax.setProperty("jndi.syntax.separator.typeval", "=");
syntax.setProperty("jndi.syntax.beginquote", "\"");
String name = "CN=Administrators,CN=Builtin,DC=example,DC=in";
CompoundName cn = new CompoundName(name, syntax);
System.out.println("DN: " + cn);
System.out.println("\nCompoundName details:\n");
for (int i = 0; i < cn.size(); i++) {
System.out.println(" " + i + " --> " + cn.get(i));
}
}
}
Even with this, you will still need to parse the individual RDNs to get the attribute values (e.g., parse "CN=Administrators" to extract the value of 'Administrators').