import javax.naming.Context;
import javax.naming.directory.InitialDirContext;
import javax.naming.directory.SearchControls;
import javax.naming.directory.SearchResult;
import javax.naming.NamingEnumeration;
import java.util.Hashtable;

public class JndiTest {
  public static void main(String[] args) throws Exception {
    Hashtable<String, String> env = new Hashtable<>();
    env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
    env.put(Context.PROVIDER_URL, "ldap://localhost:1389");
    env.put(Context.SECURITY_AUTHENTICATION, "simple");
    env.put(Context.SECURITY_PRINCIPAL, "cn=admin,dc=example,dc=org");
    env.put(Context.SECURITY_CREDENTIALS, "admin");
    InitialDirContext ctx = new InitialDirContext(env);
    SearchControls sc = new SearchControls();
    sc.setSearchScope(SearchControls.SUBTREE_SCOPE);
    NamingEnumeration<SearchResult> results = ctx.search("dc=example,dc=org", "(uid=alice)", sc);
    while (results.hasMore()) {
      SearchResult r = results.next();
      System.out.println("Found: " + r.getNameInNamespace());
    }
    ctx.close();
  }
}