TSMColumn.h

Go to the documentation of this file.

// # TSMColumn.h: A column in the Tiled Storage Manager
// # Copyright (C) 1995,1996,1997,1999
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 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 Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef TABLES_TSMCOLUMN_H
#define TABLES_TSMCOLUMN_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/tables/DataMan/StManColumnBase.h>
#include <casacore/casa/Arrays/IPosition.h>
#include <casacore/casa/BasicSL/String.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward Declarations
class TiledStMan;
class TSMDataColumn;
class TSMCoordColumn;
class TSMIdColumn;
 
// <summary>
// A column in the Tiled Storage Manager
// </summary>
 
// <use visibility=local>
 
// <reviewed reviewer="UNKNOWN" date="before2004/08/25" tests="">
// </reviewed>
 
// <prerequisite>
// # Classes you should understand before using this one.
//   <li> <linkto class=StManColumn>StManColumn</linkto>
//   <li> <linkto class=TiledStMan>TiledStMan</linkto>
// </prerequisite>
 
// <etymology>
// TSMColumn handles a column for the Tiled Storage Manager.
// </etymology>
 
// <synopsis>
// TSMColumn serves 2 purposes:
// <ol>
//  <li> It is the initial object for all columns in TiledStMan.
//  <li> It serves as a base class for the specialized TiledStMan
//       column classes dealing with data, coordinates and id values.
// </ol>
// The protocol used for creating the derived
// <linkto class=TSMDataColumn>TSMDataColumn</linkto>,
// <linkto class=TSMCoordColumn>TSMCoordColumn</linkto>, and
// <linkto class=TSMIdColumn>TSMIdColumn</linkto>
// objects is somewhat complicated. It works as follows:
// <br>
// When the table is set up, a TSMColumn object gets created for all
// columns in a TiledStMan storage manager. The TiledStMan initialization
// function lets each TSMColumn object create its specialized TSMXXColumn
// object (using make{Coord,Id,Data}Column). At the end of the setup process
// the TSMColumn objects are deleted and the DataManagerColumn pointers
// in the BaseColumn objects get replaced by those to the specialized
// objects. In that way no needless virtual function calls are done.
// </synopsis>
 
// <motivation>
// TSMColumn is needed for the initial DataManagerColumn setup process.
// It is also useful as a base class for all TiledStMan column objects.
// </motivation>
 
// # <todo asof="$DATE:$">
// # A List of bugs, limitations, extensions or planned refinements.
// # </todo>
 
class TSMColumn : public StManColumnBase {
 public:
  // Create a column of the given type.
  // It will maintain a pointer to its parent storage manager.
  TSMColumn(TiledStMan* stman, int dataType, const String& columnName);
 
  // Frees up the storage.
  virtual ~TSMColumn();
 
  // Forbid assignment.
  TSMColumn& operator=(const TSMColumn&) = delete;
 
  // Get the name of the column.
  const String& columnName() const;
 
  // Return the data type of the column.
  virtual int dataType() const;
 
  // Set the fixed shape of the column.
  void setShapeColumn(const IPosition& shape);
 
  // Get the fixed shape of the column.
  const IPosition& shapeColumn() const;
 
  // Make a TSM data column object.
  // Add the pixel length to the total data pixel length.
  TSMDataColumn* makeDataColumn();
 
  // Make a TSM coordinate column object.
  TSMCoordColumn* makeCoordColumn(uInt axesNumber);
 
  // Make a TSM id column object.
  TSMIdColumn* makeIdColumn();
 
  // Unlink the underlying column.
  // It clears the pointer and returns its original value.
  // This is used to get a pointer directly to the underlying TSMXXColumn
  // object in the BaseColumn classes. In that way only 1 instead
  // of 2 virtual function calls are needed for a get or put.
  TSMColumn* unlink();
 
 protected:
  // The storage manager.
  TiledStMan* stmanPtr_p;
  // The data type of the data (as defined in DataType.h).
  int dtype_p;
  // The name of the column.
  String name_p;
  // The fixed shape of the column.
  IPosition columnShape_p;
  // The specialized column object (i.e. data, coordinate or id).
  TSMColumn* colPtr_p;
 
  // The copy constructor can only be used to copy a derived class.
  TSMColumn(const TSMColumn& that);
};
 
inline const String& TSMColumn::columnName() const { return name_p; }
 
inline const IPosition& TSMColumn::shapeColumn() const { return columnShape_p; }
 
}  // namespace casacore
 
#endif