/*

  * $Source$

  * $Revision$

  *

  * Copyright (C) 2000 William Chesters

  *

  * 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:

  *

  *     William Chesters <williamc At paneris.org>

  *     http://paneris.org/~williamc

  *     Obrechtstraat 114, 2517VX Den Haag, The Netherlands

  */

 package org.melati.poem;

 /**

  * A {@link Column} which exists in the dbms but is not defined in the 

  * DSD.

  */

 public class ExtraColumn<T> extends Column<T> {

   private final int extrasIndex;

   /**

    * Constructor.

    */

   public <P extends Persistent> ExtraColumn(Table<P> table, String name, SQLPoemType<T> type,

                      DefinitionSource definitionSource,

                      int extrasIndex) {

     super(table, name, type, definitionSource);

     this.extrasIndex = extrasIndex;

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#getRaw(org.melati.poem.Persistent)

    */

   public T getRaw(Persistent g) throws AccessPoemException {

     ((JdbcPersistent)g).readLock();

     return getRaw_unsafe(g);

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#getRaw_unsafe(org.melati.poem.Persistent)

    */

   @SuppressWarnings("unchecked")

   public T getRaw_unsafe(Persistent g) {

     return (T)((JdbcPersistent)g).extras()[extrasIndex];

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#setRaw(org.melati.poem.Persistent, java.lang.Object)

    */

   public void setRaw(Persistent g, Object raw)

       throws AccessPoemException, ValidationPoemException {

     getType().assertValidRaw(raw);

     ((JdbcPersistent)g).writeLock();

     setRaw_unsafe(g, raw);

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#setRaw_unsafe(org.melati.poem.Persistent, java.lang.Object)

    */

   public void setRaw_unsafe(Persistent g, Object raw) {

     ((JdbcPersistent)g).extras()[extrasIndex] = raw;

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#getCooked(org.melati.poem.Persistent)

    */

   public Object getCooked(Persistent g)

       throws AccessPoemException, PoemException {

     // FIXME Revalidation  

     return getType().cookedOfRaw(getRaw(g));

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#setCooked(org.melati.poem.Persistent, java.lang.Object)

    */

   public void setCooked(Persistent g, Object cooked)

       throws AccessPoemException, ValidationPoemException {

     // FIXME Revalidation

     getType().assertValidCooked(cooked);

     setRaw(g, getType().rawOfCooked(cooked));

   }

   /**

    * {@inheritDoc}

    * @see org.melati.poem.Column#asField(org.melati.poem.Persistent)

    */

   public Field<T> asField(Persistent g) {

     try {

       return new Field<T>((T)getRaw(g), this);

     }

     catch (AccessPoemException accessException) {

       return new Field<T>(accessException, this);

     }

   }

   /**

    * Static factory.

    * @param table

    * @param columnInfo

    * @param extrasIndex

    * @param source

    * @return a new ExtraColumn 

    */

   @SuppressWarnings("unchecked")

   public static <O,P extends Persistent>Column<O> from(Table<P> table, ColumnInfo columnInfo,

                             int extrasIndex, DefinitionSource source) {

     return new ExtraColumn<O>(

         table, columnInfo.getName(), (SQLPoemType<O>)columnInfo.getType(), 

         source, extrasIndex);

   }

 }