BE THE CODER > Java > LDAP Directory Access > How to Query Specific attributes of LDAP Entry

LDAP (Lightweight Directory Access Protocol) is based on X.500 standard. Its a hierarchical data structure with Entries organized in a tree like structure called Directory Information Tree (DIT). The following example shows retrieving the specified attributes of all entries having objectclass as 'person'. The attributes such as user role and password are not grouped under default attributes. In such cases we have to explicitly specify the list of attributes to be queried.

File Name :	com/bethecoder/tutorials/ldap/QuerySpecificAttributesTest.java
Author :	Sudhakar KV
Email :	[email protected]


package com.bethecoder.tutorials.ldap;



import java.util.Hashtable;



import javax.naming.Context;

import javax.naming.NameNotFoundException;

import javax.naming.NamingEnumeration;

import javax.naming.NamingException;

import javax.naming.directory.Attribute;

import javax.naming.directory.Attributes;

import javax.naming.directory.DirContext;

import javax.naming.directory.InitialDirContext;

import javax.naming.directory.SearchControls;

import javax.naming.directory.SearchResult;





public class QuerySpecificAttributesTest {



  /**

   * @param args

   */

  public static void main(String[] args) {



    //Setup the environment to login as anonymous user

    Hashtable<String, String> environment = new Hashtable<String, String>();

    environment.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");

    environment.put(Context.PROVIDER_URL, "ldap://localhost:389/dc=test,dc=com");



    DirContext dirContext = null;

    NamingEnumeration<?> results = null;

    

    try {

      dirContext = new InitialDirContext(environment);



      /**

       * Retrieve the specific attributes 

       */

      SearchControls controls = new SearchControls();

      controls.setSearchScope(SearchControls.SUBTREE_SCOPE);

      controls.setReturningAttributes(new String [] { 

          "nsRole", //Role of user

                "uid",

                "objectClass",

                "givenName",

                "sn",

                "cn"

      });



      //Get entries having objectclass=person

      String filter = "(objectclass=person)";

      results = dirContext.search("", filter, controls);



      while (results.hasMore()) {

        SearchResult searchResult = (SearchResult) results.next();

        Attributes attributes = searchResult.getAttributes();

        

        NamingEnumeration<? extends Attribute> attrs = attributes.getAll();



        while (attrs.hasMore()) {

          System.out.println(attrs.next());

        }

        

        System.out.println();

      }



    } catch (NameNotFoundException e) {

      e.printStackTrace();

    } catch (NamingException e) {

      e.printStackTrace();

    } finally {

      if (results != null) {

        try {

          results.close();

        } catch (Exception e) {

        }

      }



      if (dirContext != null) {

        try {

          dirContext.close();

        } catch (Exception e) {

        }

      }

    }



  }



}

How to Query specific attributes of LDAP Entry