Readonly access to a table column. More...

#include <TableColumn.h>

Inheritance diagram for casa::ROTableColumn:

Public Member Functions
	ROTableColumn ()
	The default constructor creates a null object, i.e.
	ROTableColumn (const Table &, const String &columnName)
	Construct the object for a column in the table using its name.
	ROTableColumn (const Table &, uInt columnIndex)
	Construct the object for a column in the table using its index.
	ROTableColumn (const ROTableColumn &)
	Copy constructor (reference semantics).
virtual	~ROTableColumn ()
virtual ROTableColumn *	clone () const
	Clone the object.
void	reference (const ROTableColumn &)
	Change the reference to another column.
void	attach (const Table &table, const String &columnName)
	Attach a column to the object.
void	attach (const Table &table, uInt columnIndex)
Bool	isNull () const
	Test if the object is null, i.e.
void	throwIfNull () const
	Throw an exception if the object is null, i.e.
const TableRecord &	keywordSet () const
	Get readonly access to the column keyword set.
TableRecord &	rwKeywordSet ()
	Get read/write access to the column keyword set.
const ColumnDesc &	columnDesc () const
	Get const access to the column description.
Table	table () const
	Get the Table object this column belongs to.
uInt	nrow () const
	Get the number of rows in the column.
Bool	canChangeShape () const
	Can the shape of an already existing non-FixedShape array be changed? This depends on the storage manager.
uInt	ndimColumn () const
	Get the global #dimensions of an array (ie.
IPosition	shapeColumn () const
	Get the global shape of an array (ie.
Bool	isDefined (uInt rownr) const
	Test if the given cell contains a defined value.
Bool	hasContent () const
	Tests whether the column is not null and that the first cell is defined and not a degenerate Array.
uInt	ndim (uInt rownr) const
	Get the #dimensions of an array in a particular cell.
IPosition	shape (uInt rownr) const
	Get the shape of an array in a particular cell.
void	getScalar (uInt rownr, Bool &value) const
	Get the value of a scalar in the given row.
void	getScalar (uInt rownr, uChar &value) const
void	getScalar (uInt rownr, Short &value) const
void	getScalar (uInt rownr, uShort &value) const
void	getScalar (uInt rownr, Int &value) const
void	getScalar (uInt rownr, uInt &value) const
void	getScalar (uInt rownr, Int64 &value) const
void	getScalar (uInt rownr, float &value) const
void	getScalar (uInt rownr, double &value) const
void	getScalar (uInt rownr, Complex &value) const
void	getScalar (uInt rownr, DComplex &value) const
void	getScalar (uInt rownr, String &value) const
Bool	asBool (uInt rownr) const
	Get the value from the row and convert it to the required type.
uChar	asuChar (uInt rownr) const
Short	asShort (uInt rownr) const
uShort	asuShort (uInt rownr) const
Int	asInt (uInt rownr) const
uInt	asuInt (uInt rownr) const
float	asfloat (uInt rownr) const
double	asdouble (uInt rownr) const
Complex	asComplex (uInt rownr) const
DComplex	asDComplex (uInt rownr) const
String	asString (uInt rownr) const
void	getScalarValue (uInt rownr, Bool *value, const String &) const
	Get the value of a scalar in the given row.
void	getScalarValue (uInt rownr, uChar *value, const String &) const
void	getScalarValue (uInt rownr, Short *value, const String &) const
void	getScalarValue (uInt rownr, uShort *value, const String &) const
void	getScalarValue (uInt rownr, Int *value, const String &) const
void	getScalarValue (uInt rownr, uInt *value, const String &) const
void	getScalarValue (uInt rownr, float *value, const String &) const
void	getScalarValue (uInt rownr, double *value, const String &) const
void	getScalarValue (uInt rownr, Complex *value, const String &) const
void	getScalarValue (uInt rownr, DComplex *value, const String &) const
void	getScalarValue (uInt rownr, String *value, const String &) const
void	getScalarValue (uInt rownr, void *value, const String &dataTypeId) const
void	checkRowNumber (uInt rownr) const
	Check if the row number is valid.
void	setMaximumCacheSize (uInt nbytes) const
	Set the maximum cache size (in bytes) to be used by a storage manager.
Protected Member Functions
BaseColumn *	baseColPtr () const
	Get the baseColPtr_p of this ROTableColumn object.
BaseColumn *	baseColPtr (const ROTableColumn &that) const
	Get the baseColPtr_p of another ROTableColumn object.
Protected Attributes
BaseTable *	baseTabPtr_p
BaseColumn *	baseColPtr_p
const ColumnCache *	colCachePtr_p
Bool	canChangeShape_p
Private Member Functions
ROTableColumn &	operator= (const ROTableColumn &)
	Assignment makes no sense for a readonly class.
Friends
class	ForwardColumn

Detailed Description

Readonly access to a table column.

Intended use:

Public interface

Review Status

Reviewed By:: dschieb
Date Reviewed:: 1994/08/10
Test programs:: none

Prerequisite

Etymology

ROTableColumn gives readonly access to an arbitrary column in a table.

Synopsis

The class ROTableColumn gives readonly access to a column in a table. In particular access to the column description (for name, data type, etc.) and to the column keyword set can be obtained. Another important function is isDefined, which tests if a cell (i.e. table row) in a column contains a value.

The classes ROScalarColumn<T> and ROArrayColumn<T> have to be used to get the data in the column cells. However, ROTableColumn has get functions for the basic data types (Bool, uChar, Short, uSort, Int, uInt, float, double, Complex, DComplex and String). Opposite to the get functions in ROScalarColumn<T>, the ROTableColumn get functions support data type promotion.

A default constructor is defined to allow construction of an array of ROTableColumn objects. However, this constructs an object not referencing a column. Functions like get, etc. will fail (i.e. result in a segmentation fault) when used on such objects. The functions isNull and throwIfNull can be used to test on this. The functions attach and reference can fill in the object.

The assignment operator is not defined for this class, because it was felt it would be too confusing. Instead the function reference can be used to do assignment with reference semantics. An assignment with copy semantics makes no sense for a readonly column.

Example

See module Tables .

Definition at line 107 of file TableColumn.h.

Constructor & Destructor Documentation

casa::ROTableColumn::ROTableColumn ( )

The default constructor creates a null object, i.e.

it does not reference a table column. The sole purpose of this constructor is to allow construction of an array of ROTableColumn objects. The functions reference and attach can be used to make a null object reference a column. Note that get functions, etc. will cause a segmentation fault when operating on a null object. It was felt it was too expensive to test on null over and over again. The user should use the isNull or throwIfNull function in case of doubt.

casa::ROTableColumn::ROTableColumn	(	const Table &	,
		const String &	columnName
	)

Construct the object for a column in the table using its name.

casa::ROTableColumn::ROTableColumn	(	const Table &	,
		uInt	columnIndex
	)

Construct the object for a column in the table using its index.

This allows to loop through all columns in a table as:

           for (uInt=0; i<tab.ncolumn(); i++) {
               ROTableColumn tabcol(tab,i);
           }

casa::ROTableColumn::ROTableColumn ( const ROTableColumn & )

Copy constructor (reference semantics).

virtual casa::ROTableColumn::~ROTableColumn ( ) [virtual]

Member Function Documentation

Bool casa::ROTableColumn::asBool ( uInt rownr ) const

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.

Complex casa::ROTableColumn::asComplex ( uInt rownr ) const

DComplex casa::ROTableColumn::asDComplex ( uInt rownr ) const

double casa::ROTableColumn::asdouble ( uInt rownr ) const

float casa::ROTableColumn::asfloat ( uInt rownr ) const

Int casa::ROTableColumn::asInt ( uInt rownr ) const

Short casa::ROTableColumn::asShort ( uInt rownr ) const

String casa::ROTableColumn::asString ( uInt rownr ) const

uChar casa::ROTableColumn::asuChar ( uInt rownr ) const

uInt casa::ROTableColumn::asuInt ( uInt rownr ) const

uShort casa::ROTableColumn::asuShort ( uInt rownr ) const

void casa::ROTableColumn::attach	(	const Table &	table,
		const String &	columnName
	)		`[inline]`

Attach a column to the object.

This is in fact only a shorthand for <
reference (ROTableColumn (table, columnName));

Reimplemented in casa::ArrayColumn< T >, casa::ArrayColumn< Float >, casa::ArrayColumn< Double >, casa::ArrayColumn< String >, casa::ArrayColumn< Short >, casa::ArrayColumn< Int >, casa::ArrayColumn< StoredType >, casa::ArrayColumn< Bool >, casa::ArrayColumn< Complex >, casa::TableColumn, casa::ScalarColumn< T >, casa::ScalarColumn< Float >, casa::ScalarColumn< Double >, casa::ScalarColumn< String >, casa::ScalarColumn< Int >, casa::ScalarColumn< Bool >, casa::ScalarColumn< TableRecord >, casa::ScalarColumn< Complex >, casa::ROArrayColumn< T >, casa::ROArrayColumn< Float >, casa::ROArrayColumn< Double >, casa::ROArrayColumn< uChar >, casa::ROArrayColumn< String >, casa::ROArrayColumn< Short >, casa::ROArrayColumn< Int >, casa::ROArrayColumn< StoredType >, casa::ROArrayColumn< DComplex >, casa::ROArrayColumn< Bool >, casa::ROArrayColumn< Complex >, casa::ROArrayColumn< uShort >, casa::ROArrayColumn< uInt >, casa::ROScalarColumn< T >, casa::ROScalarColumn< Float >, casa::ROScalarColumn< Double >, casa::ROScalarColumn< String >, casa::ROScalarColumn< Int >, casa::ROScalarColumn< Bool >, casa::ROScalarColumn< VirtualType >, casa::ROScalarColumn< TableRecord >, casa::ROScalarColumn< Complex >, and casa::ROScalarColumn< uInt >.

Definition at line 156 of file TableColumn.h.

References reference().

void casa::ROTableColumn::attach	(	const Table &	table,
		uInt	columnIndex
	)		`[inline]`

Reimplemented in casa::TableColumn.

Definition at line 158 of file TableColumn.h.

References reference().

BaseColumn* casa::ROTableColumn::baseColPtr ( ) const [inline, protected]

Get the baseColPtr_p of this ROTableColumn object.

Definition at line 322 of file TableColumn.h.

References baseColPtr_p.

BaseColumn* casa::ROTableColumn::baseColPtr ( const ROTableColumn & that ) const [inline, protected]

Get the baseColPtr_p of another ROTableColumn object.

This is needed for function put, because baseColPtr_p is a protected member of ROTableColumn. Another TableColumn has no access to that.

Definition at line 329 of file TableColumn.h.

References baseColPtr_p.

Bool casa::ROTableColumn::canChangeShape ( ) const [inline]

Can the shape of an already existing non-FixedShape array be changed? This depends on the storage manager.

Most storage managers can handle it, but TiledDataStMan and TiledColumnStMan can not.

Definition at line 192 of file TableColumn.h.

References canChangeShape_p.

void casa::ROTableColumn::checkRowNumber ( uInt rownr ) const [inline]

Check if the row number is valid.

It throws an exception if out of range.

Definition at line 306 of file TableColumn.h.

References baseTabPtr_p, and casa::BaseTable::checkRowNumber().

virtual ROTableColumn* casa::ROTableColumn::clone ( ) const [virtual]

Clone the object.

Reimplemented in casa::ArrayColumn< T >, casa::ArrayColumn< Float >, casa::ArrayColumn< Double >, casa::ArrayColumn< String >, casa::ArrayColumn< Short >, casa::ArrayColumn< Int >, casa::ArrayColumn< StoredType >, casa::ArrayColumn< Bool >, casa::ArrayColumn< Complex >, casa::TableColumn, casa::ScalarColumn< T >, casa::ScalarColumn< Float >, casa::ScalarColumn< Double >, casa::ScalarColumn< String >, casa::ScalarColumn< Int >, casa::ScalarColumn< Bool >, casa::ScalarColumn< TableRecord >, casa::ScalarColumn< Complex >, casa::ROArrayColumn< T >, casa::ROArrayColumn< Float >, casa::ROArrayColumn< Double >, casa::ROArrayColumn< uChar >, casa::ROArrayColumn< String >, casa::ROArrayColumn< Short >, casa::ROArrayColumn< Int >, casa::ROArrayColumn< StoredType >, casa::ROArrayColumn< DComplex >, casa::ROArrayColumn< Bool >, casa::ROArrayColumn< Complex >, casa::ROArrayColumn< uShort >, casa::ROArrayColumn< uInt >, casa::ROScalarColumn< T >, casa::ROScalarColumn< Float >, casa::ROScalarColumn< Double >, casa::ROScalarColumn< String >, casa::ROScalarColumn< Int >, casa::ROScalarColumn< Bool >, casa::ROScalarColumn< VirtualType >, casa::ROScalarColumn< TableRecord >, casa::ROScalarColumn< Complex >, and casa::ROScalarColumn< uInt >.

const ColumnDesc& casa::ROTableColumn::columnDesc ( ) const

Get const access to the column description.

ColumnDesc functions have to be used to get the data type, etc.\.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		Bool &	value
	)		const `[inline]`

Get the value of a scalar in the given row.

Data type promotion is possible. These functions only work for the standard data types.

Definition at line 229 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		uChar &	value
	)		const `[inline]`

Definition at line 231 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		Short &	value
	)		const `[inline]`

Definition at line 233 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		uShort &	value
	)		const `[inline]`

Definition at line 235 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		Int &	value
	)		const `[inline]`

Definition at line 237 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		uInt &	value
	)		const `[inline]`

Definition at line 239 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		Int64 &	value
	)		const `[inline]`

Definition at line 241 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		float &	value
	)		const `[inline]`

Definition at line 243 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		double &	value
	)		const `[inline]`

Definition at line 245 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		Complex &	value
	)		const `[inline]`

Definition at line 247 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		DComplex &	value
	)		const `[inline]`

Definition at line 249 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalar	(	uInt	rownr,
		String &	value
	)		const `[inline]`

Definition at line 251 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		Bool *	value,
		const String &
	)		const `[inline]`

Get the value of a scalar in the given row.

These functions work for all data types. Data type promotion is possible for the standard data types. The functions are primarily meant for ScalarColumn<T>.

Definition at line 276 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		uChar *	value,
		const String &
	)		const `[inline]`

Definition at line 278 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		Short *	value,
		const String &
	)		const `[inline]`

Definition at line 280 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		uShort *	value,
		const String &
	)		const `[inline]`

Definition at line 282 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		Int *	value,
		const String &
	)		const `[inline]`

Definition at line 284 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		uInt *	value,
		const String &
	)		const `[inline]`

Definition at line 286 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		float *	value,
		const String &
	)		const `[inline]`

Definition at line 288 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		double *	value,
		const String &
	)		const `[inline]`

Definition at line 290 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		Complex *	value,
		const String &
	)		const `[inline]`

Definition at line 292 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		DComplex *	value,
		const String &
	)		const `[inline]`

Definition at line 294 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		String *	value,
		const String &
	)		const `[inline]`

Definition at line 296 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

void casa::ROTableColumn::getScalarValue	(	uInt	rownr,
		void *	value,
		const String &	dataTypeId
	)		const `[inline]`

Definition at line 298 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::getScalar(), and TABLECOLUMNCHECKROW.

Bool casa::ROTableColumn::hasContent ( ) const

Tests whether the column is not null and that the first cell is defined and not a degenerate Array.

Bool casa::ROTableColumn::isDefined ( uInt rownr ) const [inline]

Test if the given cell contains a defined value.

Definition at line 208 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::isDefined(), and TABLECOLUMNCHECKROW.

Bool casa::ROTableColumn::isNull ( ) const [inline]

Test if the object is null, i.e.

does not reference a column.

Definition at line 163 of file TableColumn.h.

References baseColPtr_p, casa::False, and casa::True.

Referenced by casa::TableLogSink::location(), casa::TableLogSink::message(), casa::TableLogSink::objectID(), casa::TableLogSink::priority(), and casa::TableLogSink::time().

const TableRecord& casa::ROTableColumn::keywordSet ( ) const [inline]

Get readonly access to the column keyword set.

Definition at line 171 of file TableColumn.h.

References baseColPtr_p, and casa::BaseColumn::keywordSet().

uInt casa::ROTableColumn::ndim ( uInt rownr ) const [inline]

Get the #dimensions of an array in a particular cell.

Reimplemented in casa::ROArrayColumn< T >, casa::ROArrayColumn< Float >, casa::ROArrayColumn< Double >, casa::ROArrayColumn< uChar >, casa::ROArrayColumn< String >, casa::ROArrayColumn< Short >, casa::ROArrayColumn< Int >, casa::ROArrayColumn< StoredType >, casa::ROArrayColumn< DComplex >, casa::ROArrayColumn< Bool >, casa::ROArrayColumn< Complex >, casa::ROArrayColumn< uShort >, and casa::ROArrayColumn< uInt >.

Definition at line 218 of file TableColumn.h.

References baseColPtr_p, casa::BaseColumn::ndim(), and TABLECOLUMNCHECKROW.

uInt casa::ROTableColumn::ndimColumn ( ) const [inline]

Get the global #dimensions of an array (ie.

for all cells in column). This is always set for fixed shape arrays. Otherwise, 0 will be returned.

Definition at line 198 of file TableColumn.h.

References baseColPtr_p, and casa::BaseColumn::ndimColumn().

uInt casa::ROTableColumn::nrow ( ) const [inline]

ROTableColumn& casa::ROTableColumn::operator= ( const ROTableColumn & ) [private]

Assignment makes no sense for a readonly class.

Declaring this operator private, makes it unusable.

void casa::ROTableColumn::reference ( const ROTableColumn & )

Change the reference to another column.

This is in fact an assignment operator with reference semantics. It removes the reference to the current column and creates a reference to the column referenced in the other object. It will handle null objects correctly.