Problem

You want to talk to LDAP from Java.

Solution

Java as well as Perl, PHP and plain old Shell have APIs to be able to talk to LDAP.

The Java API is probably most complex one to use – I have provided some demos on how to use the others on this site.

More will be added in time.

Example

Here is a full example of using Java's JNDI to talk to LDAP, performing a search and supplying results:

import java.util.*;
import java.io.*;
import javax.naming.*;
import javax.naming.directory.*;
import javax.naming.ldap.*;

public class getLdapDetails {

public static void main(String argv[]) {

String url="ldap://127.0.0.1:389";
Hashtable env=new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY,
"com.sun.jndi.ldap.LdapCtxFactory");
env.put(Context.PROVIDER_URL,url);
env.put(Context.SECURITY_AUTHENTICATION,"simple");
env.put(Context.SECURITY_PRINCIPAL,
"cn=Manager,dc=demo,dc=net");
env.put(Context.SECURITY_CREDENTIALS,"secret");

try {

DirContext ctx=new InitialDirContext(env);

String[] attrIDs = { "givenname","sn","mail" } ;
Attributes matchAttrs = new BasicAttributes(true); //ignore case
matchAttrs.put(new BasicAttribute("sn",argv[0]));
NamingEnumeration myenum =
ctx.search("dc=demo,dc=net",matchAttrs, attrIDs);

while( myenum.hasMore()) {

String PersonRecord="";

SearchResult result = (SearchResult)myenum.next();
Attributes attributes = result.getAttributes();

Attribute attr = attributes.get( "givenname" );
NamingEnumeration values = attr.getAll();

while( values.hasMore()) {
PersonRecord += values.next().toString();
PersonRecord += ", ";
}

attr = attributes.get( "sn" );
values = attr.getAll();

while( values.hasMore()) {
PersonRecord += values.next().toString();
PersonRecord += " - ";
}

attr = attributes.get( "mail" );
values = attr.getAll();

while( values.hasMore()) {
PersonRecord += values.next().toString();
}

System.out.println(PersonRecord);

}

ctx.close();

} catch(NamingException ne) { System.err.println(ne.toString()); }

}
}

Then a run through:


$ java getLdapDetails Doe
John, Doe - [email protected]


Reference

[tags]Java JNDI to LDAP, JNDI LDAP, LDAP Training School[/tags]

• Quick Start Guide