/*
    *
    * The DbUnit Database Testing Framework
    * Copyright (C)2002-2004, DbUnit.org
    *
    * This library is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Lesser General Public
    * License as published by the Free Software Foundation; either
    * version 2.1 of the License, or (at your option) any later version.
   *
   * This library 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   *
   */
  package org.dbunit.database;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.dbunit.dataset.Column;
  import org.dbunit.dataset.DataSetException;
  import org.dbunit.dataset.ITableMetaData;
  import org.dbunit.dataset.RowOutOfBoundsException;
  
  import java.sql.ResultSet;
  import java.sql.SQLException;
  
  /**
   * @author Manuel Laflamme
   * @since Apr 10, 2003
   * @version $Revision$
   */
  public class ForwardOnlyResultSetTable extends AbstractResultSetTable
  {
  
      /**
       * Logger for this class
       */
      private static final Logger logger = LoggerFactory.getLogger(ForwardOnlyResultSetTable.class);
  
      private int _lastRow = -1;
      private boolean _eot = false; // End of table flag
  
      public ForwardOnlyResultSetTable(ITableMetaData metaData,
              ResultSet resultSet) throws SQLException, DataSetException
      {
          super(metaData, resultSet);
      }
  
      public ForwardOnlyResultSetTable(ITableMetaData metaData,
              IDatabaseConnection connection) throws DataSetException, SQLException
      {
          super(metaData, connection);
      }
  
      public ForwardOnlyResultSetTable(String tableName, String selectStatement,
              IDatabaseConnection connection) throws DataSetException, SQLException
      {
          super(tableName, selectStatement, connection);
      }
  
      // //////////////////////////////////////////////////////////////////////////
      // ITable interface
  
      public int getRowCount()
      {
          throw new UnsupportedOperationException();
      }
  
      public Object getValue(int row, String columnName) throws DataSetException
      {
          if(logger.isDebugEnabled())
              logger.debug("getValue(row={}, columnName={}) - start", Integer.toString(row), columnName);
  
          try
          {
              // Move cursor forward up to specified row
              while (!_eot && row > _lastRow)
              {
                  _eot = !_resultSet.next();
                  _lastRow++;
              }
  
              if (row < _lastRow)
              {
                  throw new UnsupportedOperationException("Cannot go backward!");
              }
  
              if (_eot || row > _lastRow)
              {
                  // Proactively close the resultset
                  close();
                  throw new RowOutOfBoundsException(row + " > " + _lastRow);
             }
 
             int columnIndex = getColumnIndex(columnName);
             Column column = _metaData.getColumns()[columnIndex];
             return column.getDataType().getSqlValue(columnIndex + 1, _resultSet);
         }
         catch (SQLException e)
         {
             throw new DataSetException(e);
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public String toString()
     {
         StringBuilder sb = new StringBuilder(2000);
 
         sb.append(super.toString());
         sb.append(", ");
         sb.append(getClass().getName()).append("[");
         sb.append("_eot=[").append(_eot).append("], ");
         sb.append("_lastRow=[").append(_lastRow).append("]");
         sb.append("]");
 
         return sb.toString();
     }
 }