BaseColumn.h

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// # BaseColumn.h: Abstract base class for a table column
// # Copyright (C) 1994,1995,1996,1997,1998
// # 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_BASECOLUMN_H
#define TABLES_BASECOLUMN_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/tables/Tables/ColumnDesc.h>
#include <casacore/casa/Utilities/Compare.h>
#include <casacore/casa/BasicSL/Complex.h>
#include <casacore/casa/Arrays/ArrayFwd.h>
#include <memory>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward Declarations
class ArrayBase;
class BaseColumnDesc;
class ColumnCache;
class TableRecord;
class RefRows;
class IPosition;
class Slicer;
class Sort;
 
// <summary>
// Abstract base class for a table column
// </summary>
 
// <use visibility=local>
 
// <reviewed reviewer="UNKNOWN" date="before2004/08/25" tests="">
// </reviewed>
 
// <prerequisite>
// # Classes you should understand before using this one.
//   <li> ColumnDesc
//   <li> Table
// </prerequisite>
 
// <etymology>
// This is the (abstract) base class to access a column in a table.
// </etymology>
 
// <synopsis>
// This class is the base class for the derived column classes.
// It is a private class in the sense that the user cannot get
// access to it. All user access to a column is done via the
// classes TableColumn, ScalarColumn and ArrayColumn. They call
// the corresponding functions in this class and its derived classes.
// </synopsis>
 
// <motivation>
// This class serves a the base for the more specialized column classes
// like FilledScalarColumn and RefColumn. It defines many virtual
// functions, which are implemented in the derived classes.
// Some of these functions are purely virtual, some have a default
// implementation throwing an "invalid operation" exception. In that
// way those latter functions only have to be implemented in the
// classes which handle those cases.
// <note role=tip> The class RefColumn is in fact implemented in terms of
// this class. Almost every function in RefColumn calls the corresponding
// function in BaseColumn with the correct row number.
// </note>
// </motivation>
 
// <todo asof="$DATE:$">
// # A List of bugs, limitations, extensions or planned refinements.
// </todo>
 
class BaseColumn {
 public:
  // Construct it using the given column description.
  BaseColumn(const BaseColumnDesc*);
 
  virtual ~BaseColumn();
 
  // Test if the column is writable.
  virtual Bool isWritable() const = 0;
 
  // Test if the column is stored (otherwise it is virtual).
  virtual Bool isStored() const = 0;
 
  // Get access to the column keyword set.
  // <group>
  virtual TableRecord& rwKeywordSet() = 0;
  virtual TableRecord& keywordSet() = 0;
  // </group>
 
  // Get const access to the column description.
  const ColumnDesc& columnDesc() const;
 
  // Get nr of rows in the column.
  virtual rownr_t nrow() const = 0;
 
  // Test if the given cell contains a defined value.
  virtual Bool isDefined(rownr_t rownr) const = 0;
 
  // Set the shape of the array in the given row.
  virtual void setShape(rownr_t rownr, const IPosition& shape);
 
  // Set the shape and tile shape of the array in the given row.
  virtual void setShape(rownr_t rownr, const IPosition& shape, const IPosition& tileShape);
 
  // Get the global #dimensions of an array (ie. for all rows).
  virtual uInt ndimColumn() const;
 
  // Get the global shape of an array (ie. for all rows).
  virtual IPosition shapeColumn() const;
 
  // Get the #dimensions of an array in a particular cell.
  virtual uInt ndim(rownr_t rownr) const;
 
  // Get the shape of an array in a particular cell.
  virtual IPosition shape(rownr_t rownr) const;
 
  // Get the tile shape of an array in a particular cell.
  virtual IPosition tileShape(rownr_t rownr) const;
 
  // Ask the data manager if the shape of an existing array can be changed.
  // Default is no.
  virtual Bool canChangeShape() const;
 
  // Initialize the rows from startRow till endRow (inclusive)
  // with the default value defined in the column description.
  virtual void initialize(rownr_t startRownr, rownr_t endRownr) = 0;
 
  // Get a scalar value from a particular cell.
  virtual void get(rownr_t rownr, void* dataPtr) const;
 
  // Get an array from a particular cell.
  virtual void getArray(rownr_t rownr, ArrayBase& dataPtr) const;
 
  // Get a slice of an N-dimensional array in a particular cell.
  virtual void getSlice(rownr_t rownr, const Slicer&, ArrayBase& dataPtr) const;
 
  // Get the vector of all scalar values in a column.
  virtual void getScalarColumn(ArrayBase& dataPtr) const;
 
  // Get the array of all array values in a column.
  // If the column contains n-dim arrays, the resulting array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void getArrayColumn(ArrayBase& dataPtr) const;
 
  // Get subsections from all arrays in the column.
  // If the column contains n-dim arrays, the resulting array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void getColumnSlice(const Slicer&, ArrayBase& dataPtr) const;
 
  // Get the vector of some scalar values in a column.
  virtual void getScalarColumnCells(const RefRows& rownrs, ArrayBase& dataPtr) const;
 
  // Get the array of some array values in a column.
  // If the column contains n-dim arrays, the resulting array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void getArrayColumnCells(const RefRows& rownrs, ArrayBase& dataPtr) const;
 
  // Get subsections from some arrays in the column.
  // If the column contains n-dim arrays, the resulting array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void getColumnSliceCells(const RefRows& rownrs, const Slicer&, ArrayBase& dataPtr) const;
 
  // Put the scalar value in a particular cell.
  virtual void put(rownr_t rownr, const void* dataPtr);
 
  // Put the array value in a particular cell.
  virtual void putArray(rownr_t rownr, const ArrayBase& dataPtr);
 
  // Put a slice of an N-dimensional array in a particular cell.
  virtual void putSlice(rownr_t rownr, const Slicer&, const ArrayBase& dataPtr);
 
  // Put the vector of all scalar values in the column.
  virtual void putScalarColumn(const ArrayBase& dataPtr);
 
  // Put the array of all array values in the column.
  // If the column contains n-dim arrays, the source array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void putArrayColumn(const ArrayBase& dataPtr);
 
  // Put into subsections of all table arrays in the column.
  // If the column contains n-dim arrays, the source array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void putColumnSlice(const Slicer&, const ArrayBase& dataPtr);
 
  // Get the vector of some scalar values in a column.
  virtual void putScalarColumnCells(const RefRows& rownrs, const ArrayBase& dataPtr);
 
  // Get the array of some array values in a column.
  // If the column contains n-dim arrays, the resulting array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void putArrayColumnCells(const RefRows& rownrs, const ArrayBase& dataPtr);
 
  // Put subsections of some arrays in the column.
  // If the column contains n-dim arrays, the source array is (n+1)-dim.
  // The arrays in the column have to have the same shape in all cells.
  virtual void putColumnSliceCells(const RefRows& rownrs, const Slicer&, const ArrayBase& dataPtr);
 
  // Get the value from the row and convert it to the required type.
  // This can only be used for scalar columns with a standard data type.
  // Note that an unsigned integer cannot be converted to a signed integer
  // with the same length. So only Int64 can handle all integer values.
  // <group>
  void getScalar(rownr_t rownr, Bool& value) const;
  void getScalar(rownr_t rownr, uChar& value) const;
  void getScalar(rownr_t rownr, Short& value) const;
  void getScalar(rownr_t rownr, uShort& value) const;
  void getScalar(rownr_t rownr, Int& value) const;
  void getScalar(rownr_t rownr, uInt& value) const;
  void getScalar(rownr_t rownr, Int64& value) const;
  void getScalar(rownr_t rownr, float& value) const;
  void getScalar(rownr_t rownr, double& value) const;
  void getScalar(rownr_t rownr, Complex& value) const;
  void getScalar(rownr_t rownr, DComplex& value) const;
  void getScalar(rownr_t rownr, String& value) const;
  void getScalar(rownr_t rownr, TableRecord& value) const;
  // </group>
 
  // Get a scalar for the other data types.
  // The given data type id must match the data type id of this column.
  void getScalar(rownr_t rownr, void* value, const String& dataTypeId) const;
 
  // Put the value into the row and convert it from the given type.
  // This can only be used for scalar columns with a standard data type.
  // <group>
  void putScalar(rownr_t rownr, const Bool& value);
  void putScalar(rownr_t rownr, const uChar& value);
  void putScalar(rownr_t rownr, const Short& value);
  void putScalar(rownr_t rownr, const uShort& value);
  void putScalar(rownr_t rownr, const Int& value);
  void putScalar(rownr_t rownr, const uInt& value);
  void putScalar(rownr_t rownr, const Int64& value);
  void putScalar(rownr_t rownr, const float& value);
  void putScalar(rownr_t rownr, const double& value);
  void putScalar(rownr_t rownr, const Complex& value);
  void putScalar(rownr_t rownr, const DComplex& value);
  void putScalar(rownr_t rownr, const String& value);
  void putScalar(rownr_t rownr, const Char* value) { putScalar(rownr, String(value)); }
  void putScalar(rownr_t rownr, const TableRecord& value);
  // </group>
 
  // Get a pointer to the underlying column cache.
  virtual ColumnCache& columnCache() = 0;
 
  // Set the maximum cache size (in bytes) to be used by a storage manager.
  virtual void setMaximumCacheSize(uInt nbytes) = 0;
 
  // Add this column and its data to the Sort object.
  // It may allocate some storage on the heap, which will be saved
  // in the argument dataSave.
  // The function freeSortKey must be called to free this storage.
  // <group>
  virtual void makeSortKey(Sort&, std::shared_ptr<BaseCompare>& cmpObj, Int order,
                           std::shared_ptr<ArrayBase>& dataSave);
  // Do it only for the given row numbers.
  virtual void makeRefSortKey(Sort&, std::shared_ptr<BaseCompare>& cmpObj, Int order,
                              const Vector<rownr_t>& rownrs, std::shared_ptr<ArrayBase>& dataSave);
  // </group>
 
  // Allocate value buffers for the table iterator.
  // Also get a comparison object if undefined.
  // The function freeIterBuf must be called to free the buffers.
  virtual void allocIterBuf(void*& lastVal, void*& curVal, std::shared_ptr<BaseCompare>& cmpObj);
 
  // Free the value buffers allocated by allocIterBuf.
  virtual void freeIterBuf(void*& lastVal, void*& curVal);
 
 protected:
  // Throw exceptions for invalid scalar get or put.
  // <group>
  void throwGetScalar() const;
  void throwPutScalar() const;
  void throwGetType(const String& type) const;
  void throwPutType(const String& type) const;
  // </group>
 
  // # Data members
  const BaseColumnDesc* colDescPtr_p;
 
 private:
  // # This ColumnDesc object is created to be able to return
  // # a const ColumnDesc& by function columnDesc().
  mutable ColumnDesc colDesc_p;
};
 
}  // namespace casacore
 
#endif