/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.acegisecurity.providers.jaas;

 import org.acegisecurity.Authentication;

 import org.acegisecurity.userdetails.UserDetails;

 import java.io.IOException;

 import javax.security.auth.callback.Callback;

 import javax.security.auth.callback.NameCallback;

 import javax.security.auth.callback.UnsupportedCallbackException;

 /**

  * The most basic Callbacks to be handled when using a LoginContext from JAAS, are the NameCallback and

  * PasswordCallback. The acegi security framework provides the JaasNameCallbackHandler specifically tailored to

  * handling the NameCallback. <br>

  *

  * @author Ray Krueger

  * @version $Id: JaasNameCallbackHandler.java 1496 2006-05-23 13:38:33Z benalex $

  *

  * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/javax/security/auth/callback/Callback.html">Callback</a>

  * @see <a

  *      href="http://java.sun.com/j2se/1.4.2/docs/api/javax/security/auth/callback/NameCallback.html">NameCallback</a>

  */

 public class JaasNameCallbackHandler implements JaasAuthenticationCallbackHandler {

     //~ Methods ========================================================================================================

     /**

      * If the callback passed to the 'handle' method is an instance of NameCallback, the

      * JaasNameCallbackHandler will call, callback.setName(authentication.getPrincipal().toString()).

      *

      * @param callback

      * @param authentication

      *

      * @throws IOException

      * @throws UnsupportedCallbackException

      */

     public void handle(Callback callback, Authentication authentication)

         throws IOException, UnsupportedCallbackException {

         if (callback instanceof NameCallback) {

             NameCallback ncb = (NameCallback) callback;

             String username = "";

             Object principal = authentication.getPrincipal();

             if (principal instanceof UserDetails) {

                 username = ((UserDetails) principal).getUsername();

             } else {

                 username = principal.toString();

             }

             ncb.setName(username);

         }

     }

 }