/*

  * $Source$

  * $Revision$

  *

  * Copyright (C) 2007 Tim Pizey

  *

  * Part of Melati (http://melati.org), a framework for the rapid

  * development of clean, maintainable web applications.

  *

  * Melati is free software; Permission is granted to copy, distribute

  * and/or modify this software under the terms either:

  *

  * a) the GNU General Public License as published by the Free Software

  *    Foundation; either version 2 of the License, or (at your option)

  *    any later version,

  *

  *    or

  *

  * b) any version of the Melati Software License, as published

  *    at http://melati.org

  *

  * You should have received a copy of the GNU General Public License and

  * the Melati Software License along with this program;

  * if not, write to the Free Software Foundation, Inc.,

  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the

  * GNU General Public License and visit http://melati.org to obtain the

  * Melati Software License.

  *

  * Feel free to contact the Developers of Melati (http://melati.org),

  * if you would like to work out a different arrangement than the options

  * outlined here.  It is our intention to allow Melati to be used by as

  * wide an audience as possible.

  *

  * This program is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  *

  * Contact details for copyright holder:

  *

  *     Tim Pizey <timp At paneris.org>

  *     http://paneris.org/~timp

  */

 package org.melati.poem;

 import java.util.Comparator;

 import java.util.Enumeration;

 import java.util.NoSuchElementException;

 import java.util.SortedMap;

 /**

  * @author timp

  * @since 8 Jun 2007

  *

  */

 public class TableSortedMap<P extends Persistent> extends TableMap<P> 

     implements SortedMap<Integer, P> {

   /**

    * Constructor for setter injection.

    */

   public TableSortedMap() {

   }

   /**

    * Constructor for constructor injection.

    * @param t

    */

   public TableSortedMap(Table<P> t) {

     super(t);

   }

   /**

    * We use native ordering. 

    */

   @Override

   public Comparator<Integer> comparator() {

     return null;

   }

   @Override

   public Integer firstKey() {

     if(table.cachedCount((String)null).count() == 0) 

       throw new NoSuchElementException();

     try { 

       table.getObject(0);

       return new Integer(0);

     } catch (NoSuchRowPoemException e) { 

       Persistent p = table.firstSelection(null);

       return p.troid();

     }

   }

   /** 

    * {@inheritDoc}

    * 

    * NOTE first attempt using table.getMostRecentTroid() does not take 

    * account of deletion as mostRecentTroid is never decremented 

    * @see java.util.SortedMap#lastKey()

    */

   @Override

   public Integer lastKey() {

     if(table.cachedCount((String)null).count() == 0) 

       throw new NoSuchElementException();

     Enumeration<P> them  = table.selection(null, table.getDatabase().getDbms().getQuotedName("id") + " DESC", false);

     return them.nextElement().troid();

   }

   @Override

   public SortedMap<Integer, P> subMap(Integer fromKey, Integer toKey) {

     throw new UnsupportedOperationException();

   }

   @Override

   public SortedMap<Integer, P> headMap(Integer toKey) {

     throw new UnsupportedOperationException();

   }

   @Override

   public SortedMap<Integer, P> tailMap(Integer arg0) {

     throw new UnsupportedOperationException();

   }

 }