001    /* NamingEnumeration.java -- The JNDI enumeration
002       Copyright (C) 2000, 2006 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038     
039    package javax.naming;
040    
041    import java.util.Enumeration;
042    
043    /**
044     * <p>The specific type of enumeration that supports throwing various exceptions by
045     * the hasMore method. The exceptions are only thrown if the enumeration is
046     * scanned using {@link #next()} and {@link #hasMore()}. If the inherited
047     * {@link java.util.Enumeration#nextElement()} and
048     * {@link Enumeration#hasMoreElements()} are used instead, the exceptions are
049     * not throwed, and the enumeration is just iterated over available elements.
050     * </p>
051     * <p>This enumeration becomes invalid after throwing the exception. If the
052     * exception has been thrown, not other method should be called of that
053     * enumeration.</p>
054     */
055    public interface NamingEnumeration<T> extends Enumeration<T>
056    {
057      /**
058       * Returns the next element in this enumeration. The naming - specific
059       * exceptions are only throws after returning all still available elements of
060       * the enumeration.
061       * 
062       * @return the next element of this enumeration
063       * @throws NamingException
064       */
065      T next() throws NamingException;
066      
067      /**
068       * Checks if there are more unvisited elements in the enumeration, throwing
069       * exceptions if there are some unvisited, but not available elements.
070       * 
071       * @return true if there are some unvisited elements, false otherwise.
072       * @throws PartialResultException if the enumeration, returned by the
073       *           {@link Context#list(Name)} or other similar method contains only
074       *           partial answer.
075       * @throws SizeLimitExceededException if remaining elements are not available
076       *           because of the previously specified size limit.
077       * @throws NamingException
078       */
079      boolean hasMore() throws NamingException;
080      
081      /**
082       * Immediately frees all resources, owned by this enumeration. If invoked, it
083       * must be the last method called for that enumeration.
084       * 
085       * @throws NamingException
086       */  
087      void close() throws NamingException;
088    
089    }