001    /*
002      Copyright (C) 2001-2002 Laurent Martelli <laurent@aopsys.com>
003      
004      This program is free software; you can redistribute it and/or modify
005      it under the terms of the GNU Lesser General Public License as
006      published by the Free Software Foundation; either version 2 of the
007      License, or (at your option) any later version.
008    
009      This program is distributed in the hope that it will be useful,
010      but WITHOUT ANY WARRANTY; without even the implied warranty of
011      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
012      GNU Lesser General Public License for more details.
013    
014      You should have received a copy of the GNU Lesser General Public License
015      along with this program; if not, write to the Free Software
016      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
017    
018    package org.objectweb.jac.aspects.authentication;
019    
020    /**
021     * The role of a class that implements this interface is to ensure
022     * that the <code>AuthenticationAC.USER</code> contextual attribute
023     * corresponds to an authenticated user (an existing user). */
024    
025    public interface Authenticator {   
026        /**
027         * Authenticates the current user.
028         * @return the username of the user.
029         */
030        String authenticate() throws AuthenticationFailedException;
031    }