casacore::TableKeyword Class Reference

Keyword value representing a table. More...

#include <TableKeyword.h>

Public Member Functions
	TableKeyword (const String &tableDescName)
	Construct a TableKeyword with the given tableDescName.
	TableKeyword (const Table &table, const String &tableDescName)
	Construct a TableKeyword from a Table.
	TableKeyword (const TableKeyword &that)
	Copy constructor (full copy semantics).
TableKeyword &	operator= (const TableKeyword &that)
	Assignment (leaves tableDescName_p untouched).
TableKeyword &	operator= (const Table &table)
	~TableKeyword ()
void	set (const String &name, const TableAttr &parentAttr)
	Set the name of the table and the writable switch.
void	setRW ()
	Set the keyword to read/write access.
Bool	isMultiUsed (Bool checkSubTables) const
	Is the table in use in another process? If `checkSubTables` is set, it is also checked if a subtable is used in another process.
const String &	tableName () const
	Get the name of the table.
String	tableName (const String &parentName) const
	Get the name of the table relative to parent table.
String	tableName (const TableAttr &parentAttr) const
Table	table (const TableLock *lockOptions=0) const
	Get the table.
const TableAttr &	tableAttributes () const
	Get the table attributes.
void	setTableAttributes (const TableAttr &attr)
	Set the table attributes.
void	close () const
	Close the table.
void	flush (Bool fsync) const
	Flush and optionally fsync the table.
void	renameTable (const String &newParentName, const String &oldParentName)
	Rename the table if its path contains the old parent table name.
Bool	conform (const TableKeyword &that) const
	Test if the table in other conforms this table keyword.
Bool	conform (const Table &that) const
Bool	isFixed () const
	Has the table a fixed description name? It has when its description name is not empty.
Private Attributes
Table *	table_p
TableAttr	attr_p
String	tableDescName_p

Detailed Description

Keyword value representing a table.

Intended use:

Internal

Review Status

Reviewed By:: Mark Wieringa
Date Reviewed:: 1996/04/15
Test programs:: tTableRecord

Prerequisite

Synopsis

TableKeyword represents a record keyword field containing a table. It is used by class TableRecord, which in its turn is meant to be used by the Table class. It serves the following purposes:

A table is only opened on demand, i.e. when the keyword is accessed for the first time. When opened, the function closeTable makes it possible to close a table when not needed anymore (provided the table is not used elsewhere). It will automatically be reopened when used again.
A switch is maintained which indicates if the table should be opened as readonly or read/write. A table is opened as read/write when the switch is read/write and when the table is writable. Otherwise it is opened as readonly. When a parent table is read back, its TableKeyword's will be read back and the switch will be set to the access-mode (readonly or read/write) of the parent table. When a new table is inserted, the access-mode is taken from the table.
When the parent table is reopened as read/write, the table in this object will also be reopened as read/write (if the table is writable).
When a TableKeyword gets written, only the table name will be written. Reading it back will set the correct access-mode, while the table will not be opened until necessary. However, when reading a parent table back it is possible that it is done from a different directory than where it was created. Therefore the directory of the parent table is prepended to the TableKeyword subtable name. Similarly, when written it is stripped off.
E.g. parent table XX and subtable SUB are created in the working directory WD. Reading back is done from another directory by specifying WD/XX. WD will be prepended to SUB.

Motivation

This class provides the extra functionality for keywords containing tables. This is needed because tables are much more complex entities than scalars or arrays.

Example

 // Store a table in the keyword set.
 void someFunc (const Table& subTable)
 {
 // Open the table and get access to the table keyword set.
 Table table("table.data", Table::Update);
 TableRecord& keyset = table.rwKeywordSet();
 keyset.defineTable ("KeyTab", subTable);
 }
 
 // Open the table and get the table from keyword KeyTab.
 // It shows that this can be done in one statement.
 Table table("table.data");
 Table subTab = table.keywordSet().asTable ("KeyTab");

Definition at line 121 of file TableKeyword.h.

Constructor & Destructor Documentation

casacore::TableKeyword::TableKeyword ( const String & tableDescName )

Construct a TableKeyword with the given tableDescName.

When the tableDescName is empty the keyword is variable structured. Otherwise it is fixed structured, meaning that only tables with a description of that name can be assigned to this keyword.

casacore::TableKeyword::TableKeyword	(	const Table &	table,
		const String &	tableDescName
	)

Construct a TableKeyword from a Table.

When the tableDescName is empty the keyword is variable structured. Otherwise it is fixed structured, meaning that only tables with a description of that name can be assigned to this keyword.

casacore::TableKeyword::TableKeyword ( const TableKeyword & that )

Copy constructor (full copy semantics).

casacore::TableKeyword::~TableKeyword ( )

Member Function Documentation

void casacore::TableKeyword::close ( ) const

Close the table.

Bool casacore::TableKeyword::conform ( const Table & that ) const

Bool casacore::TableKeyword::conform ( const TableKeyword & that ) const

Test if the table in other conforms this table keyword.

It conforms when this description name is blank or matches the table description name of the other.

void casacore::TableKeyword::flush ( Bool fsync ) const

Flush and optionally fsync the table.

Bool casacore::TableKeyword::isFixed ( ) const [inline]

Has the table a fixed description name? It has when its description name is not empty.

Definition at line 222 of file TableKeyword.h.

References casacore::String::empty(), and tableDescName_p.

Bool casacore::TableKeyword::isMultiUsed ( Bool checkSubTables ) const

Is the table in use in another process? If checkSubTables is set, it is also checked if a subtable is used in another process.

TableKeyword& casacore::TableKeyword::operator= ( const Table & table )

TableKeyword& casacore::TableKeyword::operator= ( const TableKeyword & that )

Assignment (leaves tableDescName_p untouched).

This is only possible when both objects conform.

void casacore::TableKeyword::renameTable	(	const String &	newParentName,
		const String &	oldParentName
	)

Rename the table if its path contains the old parent table name.

void casacore::TableKeyword::set	(	const String &	name,
		const TableAttr &	parentAttr
	)

Set the name of the table and the writable switch.

This is used when reading back a keyword.

void casacore::TableKeyword::setRW ( )

Set the keyword to read/write access.

If the table is already open, it will be reopened with read/write access if the table is writable.

void casacore::TableKeyword::setTableAttributes ( const TableAttr & attr ) [inline]

Set the table attributes.

Definition at line 184 of file TableKeyword.h.

References attr_p.

Table casacore::TableKeyword::table ( const TableLock * lockOptions = 0 ) const

Get the table.

It will be opened when necessary. If given, the lockOptions will be used instead of the ones in the table attributes.

const TableAttr& casacore::TableKeyword::tableAttributes ( ) const [inline]

Get the table attributes.

Definition at line 180 of file TableKeyword.h.

References attr_p.

String casacore::TableKeyword::tableName ( const TableAttr & parentAttr ) const [inline]

Definition at line 169 of file TableKeyword.h.

References casacore::TableAttr::name(), and tableName().

Referenced by tableName().

String casacore::TableKeyword::tableName ( const String & parentName ) const

Get the name of the table relative to parent table.

const String & casacore::TableKeyword::tableName ( ) const [inline]

Get the name of the table.

Definition at line 217 of file TableKeyword.h.

References attr_p, and casacore::TableAttr::name().

Member Data Documentation

TableAttr casacore::TableKeyword::attr_p [private]

Definition at line 211 of file TableKeyword.h.

Referenced by setTableAttributes(), tableAttributes(), and tableName().

Table* casacore::TableKeyword::table_p [private]

Definition at line 210 of file TableKeyword.h.

String casacore::TableKeyword::tableDescName_p [private]

Definition at line 212 of file TableKeyword.h.

Referenced by isFixed().

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

casacore/tables/Tables/TableKeyword.h