Access to a table column containing scalars. More...

#include <ScaColData.h>

Inheritance diagram for casa::ScalarColumnData< T >:

Public Member Functions
	ScalarColumnData (const ScalarColumnDesc< T > , ColumnSet )
	Construct a scalar column object from the given description in the given column set.
	~ScalarColumnData ()
Bool	canAccessScalarColumn (Bool &reask) const
	Ask if the data manager can handle a column.
Bool	canAccessScalarColumnCells (Bool &reask) const
	Ask if the data manager can handle some cells in a column.
void	initialize (uInt startRownr, uInt endRownr)
	Initialize the rows from startRownr till endRownr (inclusive) with the default value defined in the column description.
Bool	isDefined (uInt rownr) const
	Test if the given cell contains a defined value.
void	get (uInt rownr, void *) const
	Get the value from a particular cell.
void	getScalarColumn (void *dataPtr) const
	Get the array of all values in the column.
void	getScalarColumnCells (const RefRows &rownrs, void *dataPtr) const
	Get the array of some values in the column (on behalf of RefColumn).
void	put (uInt rownr, const void *dataPtr)
	Put the value in a particular cell.
void	putScalarColumn (const void *dataPtr)
	Put the array of all values in the column.
void	putScalarColumnCells (const RefRows &rownrs, const void *dataPtr)
	Put the array of some values in the column (on behalf on RefColumn).
void	makeSortKey (Sort &, CountedPtr< BaseCompare > &cmpFunc, Int order, const void *&dataSave)
	Add this column and its data to the Sort object.
void	makeRefSortKey (Sort &, CountedPtr< BaseCompare > &cmpFunc, Int order, const Vector< uInt > &rownrs, const void *&dataSave)
	Do it only for the given row numbers.
void	freeSortKey (const void *&dataSave)
	Free storage on the heap allocated by makeSortkey().
void	allocIterBuf (void &lastVal, void &curVal, CountedPtr< BaseCompare > &cmpObj)
	Allocate value buffers for the table iterator.
void	freeIterBuf (void &lastVal, void &curVal)
	Free the value buffers allocated by allocIterBuf.
void	createDataManagerColumn ()
	Create a data manager column object for this column.
Private Member Functions
	ScalarColumnData (const ScalarColumnData< T > &)
	Copy constructor cannot be used.
ScalarColumnData< T > &	operator= (const ScalarColumnData< T > &)
	Assignment cannot be used.
void	putFileDerived (AipsIO &)
	Write the column data.
void	getFileDerived (AipsIO &, const ColumnSet &)
	Read the column data back.
void	fillSortKey (const Vector< T > *dataPtr, Sort &, CountedPtr< BaseCompare > &cmpObj, Int order)
	Fill in the sort key on behalf of the Table sort function.
Private Attributes
const ScalarColumnDesc< T > *	scaDescPtr_p
	Pointer to column description.
Bool	undefFlag_p
	Undefined value can exist?
T	undefVal_p
	Undefined value.

Detailed Description

template<class T>
class casa::ScalarColumnData< T >

Access to a table column containing scalars.

Intended use:

Internal

Review Status

Reviewed By:: Gareth Hunt
Date Reviewed:: 94Nov17

Prerequisite

Etymology

ScalarColumnData represents a table column containing scalars.

Synopsis

The class ScalarColumnData is derived from PlainColumn. It implements the virtual functions accessing a table column containing scalars with an arbitrary data type.

It is possible to access an scalar an individual cell (i.e. table row) or in the entire column.

The main task of this class is to communicate with the data manager column object. This consists of:

Binding itself to a data manager.
Letting the data manager create its column object.
Closing the data manager column object (in putFileDerived).
Reconstructing the data manager object for an existing table (in getFileDerived).
Transferring get/put calls to the data manager column object.

The class is hidden from the user by the envelope class ScalarColumn. It used directly, it should be done with care. It assumes that the arrays in the various get and put functions have the correct length. ScalarColumn does that check.

Definition at line 95 of file ScaColData.h.

Constructor & Destructor Documentation

template<class T>

casa::ScalarColumnData< T >::ScalarColumnData	(	const ScalarColumnDesc< T > *	,
		ColumnSet *
	)

Construct a scalar column object from the given description in the given column set.

This constructor is used by ScalarColumnDesc::makeColumn.

template<class T>

casa::ScalarColumnData< T >::~ScalarColumnData ( )

template<class T>

casa::ScalarColumnData< T >::ScalarColumnData ( const ScalarColumnData< T > & ) [private]

Copy constructor cannot be used.

Member Function Documentation

template<class T>

void casa::ScalarColumnData< T >::allocIterBuf	(	void *&	lastVal,
		void *&	curVal,
		CountedPtr< BaseCompare > &	cmpObj
	)		`[virtual]`

Allocate value buffers for the table iterator.

Also get a comparison object if undefined. The function freeIterBuf must be called to free the buffers.

Reimplemented from casa::BaseColumn.

template<class T>

Bool casa::ScalarColumnData< T >::canAccessScalarColumn ( Bool & reask ) const [virtual]

Ask if the data manager can handle a column.

Reimplemented from casa::BaseColumn.

template<class T>

Bool casa::ScalarColumnData< T >::canAccessScalarColumnCells ( Bool & reask ) const [virtual]

Ask if the data manager can handle some cells in a column.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::createDataManagerColumn ( ) [virtual]

Create a data manager column object for this column.

Implements casa::PlainColumn.

template<class T>

void casa::ScalarColumnData< T >::fillSortKey	(	const Vector< T > *	dataPtr,
		Sort &	,
		CountedPtr< BaseCompare > &	cmpObj,
		Int	order
	)		`[private]`

Fill in the sort key on behalf of the Table sort function.

The pointer to the data (which can be allocated on the heap) is stored in dataPtr. This is used by freeSortKey to release it. It checks if a compare function is given when needed.

Thrown Exceptions

TableInvSort

template<class T>

void casa::ScalarColumnData< T >::freeIterBuf	(	void *&	lastVal,
		void *&	curVal
	)		`[virtual]`

Free the value buffers allocated by allocIterBuf.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::freeSortKey ( const void *& dataSave ) [virtual]

Free storage on the heap allocated by makeSortkey().

The pointer will be set to zero.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::get	(	uInt	rownr,
		void *
	)		const `[virtual]`

Get the value from a particular cell.

Implements casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::getFileDerived	(	AipsIO &	,
		const ColumnSet &
	)		`[private, virtual]`

Read the column data back.

The control information is read from the given AipsIO object. This is used to bind the column to the appropriate data manager. Thereafter the data manager gets opened.

Implements casa::PlainColumn.

template<class T>

void casa::ScalarColumnData< T >::getScalarColumn ( void * dataPtr ) const [virtual]

Get the array of all values in the column.

The length of the buffer pointed to by dataPtr must match the actual length. This is checked by ScalarColumn.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::getScalarColumnCells	(	const RefRows &	rownrs,
		void *	dataPtr
	)		const `[virtual]`

Get the array of some values in the column (on behalf of RefColumn).

The length of the buffer pointed to by dataPtr must match the actual length. This is checked by ScalarColumn.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::initialize	(	uInt	startRownr,
		uInt	endRownr
	)		`[virtual]`

Initialize the rows from startRownr till endRownr (inclusive) with the default value defined in the column description.

Implements casa::BaseColumn.

template<class T>

Bool casa::ScalarColumnData< T >::isDefined ( uInt rownr ) const [virtual]

Test if the given cell contains a defined value.

Implements casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::makeRefSortKey	(	Sort &	,
		CountedPtr< BaseCompare > &	cmpFunc,
		Int	order,
		const Vector< uInt > &	rownrs,
		const void *&	dataSave
	)		`[virtual]`

Do it only for the given row numbers.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::makeSortKey	(	Sort &	,
		CountedPtr< BaseCompare > &	cmpFunc,
		Int	order,
		const void *&	dataSave
	)		`[virtual]`

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.

Thrown Exceptions

TableInvSort

Reimplemented from casa::BaseColumn.

template<class T>

ScalarColumnData<T>& casa::ScalarColumnData< T >::operator= ( const ScalarColumnData< T > & ) [private]

Assignment cannot be used.

template<class T>

void casa::ScalarColumnData< T >::put	(	uInt	rownr,
		const void *	dataPtr
	)		`[virtual]`

Put the value in a particular cell.

The length of the buffer pointed to by dataPtr must match the actual length. This is checked by ScalarColumn.

Implements casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::putFileDerived ( AipsIO & ) [private, virtual]

Write the column data.

The control information is written into the given AipsIO object, while the data is written/flushed by the data manager.

Implements casa::PlainColumn.

template<class T>

void casa::ScalarColumnData< T >::putScalarColumn ( const void * dataPtr ) [virtual]

Put the array of all values in the column.

The length of the buffer pointed to by dataPtr must match the actual length. This is checked by ScalarColumn.

Reimplemented from casa::BaseColumn.

template<class T>

void casa::ScalarColumnData< T >::putScalarColumnCells	(	const RefRows &	rownrs,
		const void *	dataPtr
	)		`[virtual]`

Put the array of some values in the column (on behalf on RefColumn).

The length of the buffer pointed to by dataPtr must match the actual length. This is checked by ScalarColumn.

Reimplemented from casa::BaseColumn.

Member Data Documentation

template<class T>

const ScalarColumnDesc<T>* casa::ScalarColumnData< T >::scaDescPtr_p [private]

Pointer to column description.

Definition at line 181 of file ScaColData.h.

template<class T>

Bool casa::ScalarColumnData< T >::undefFlag_p [private]

Undefined value can exist?

Definition at line 183 of file ScaColData.h.

template<class T>

T casa::ScalarColumnData< T >::undefVal_p [private]

Undefined value.

Definition at line 185 of file ScaColData.h.

The documentation for this class was generated from the following file:

casacore/tables/Tables/ScaColData.h

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

template<class T> class casa::ScalarColumnData< T >

Intended use:

Review Status

Prerequisite

Etymology

Synopsis

Constructor & Destructor Documentation

Member Function Documentation

Thrown Exceptions

Thrown Exceptions

Member Data Documentation

template<class T>
class casa::ScalarColumnData< T >