casacore::TableSyncData Class Reference

Class to hold table synchronization data. More...

#include <TableSyncData.h>

Public Member Functions
	TableSyncData ()
	~TableSyncData ()
void	write (rownr_t nrrow, uInt nrcolumn, Bool tableChanged, const Block< Bool > &dataManChanged)
	Update the synchronization data and write it into the MemoryIO object. More...
void	write (rownr_t nrrow)
	Update the synchronization data and write it into the MemoryIO object. More...
Bool	read (rownr_t &nrrow, uInt &nrcolumn, Bool &tableChanged, Block< Bool > &dataManChanged)
	Read the synchronization data from the MemoryIO object. More...
MemoryIO &	memoryIO ()
	Get the MemoryIO object. More...
uInt	getModifyCounter () const
	Get the modify counter. More...

Private Member Functions
	TableSyncData (const TableSyncData &that)
	Copy constructor is forbidden. More...
TableSyncData &	operator= (const TableSyncData &that)
	Assignment is forbidden. More...

Private Attributes
rownr_t	itsNrrow
Int	itsNrcolumn
uInt	itsModifyCounter
uInt	itsTableChangeCounter
Block< uInt >	itsDataManChangeCounter
MemoryIO	itsMemIO
AipsIO	itsAipsIO

Detailed Description

Class to hold table synchronization data.

Intended use:

Internal

Review Status

Reviewed By:

UNKNOWN

Date Reviewed:

before2004/08/25

Test programs:

tTable

Prerequisite

• class TableLockData

Synopsis

This class keeps counters to synchronize the table data when a table is locked or unlocked.
A few counters are kept by this class:

• The numbers of rows in the table.
• The number of columns in the table.
• The table change counter.
• A change counter per data manager.

When a lock on the table is acquired, it reads the sync data from the lock file and determines if anything has changed. If so, the necessary steps are taken to reread the table data when needed.
When a lock on the table is released, it updates and writes the sync data which tells if table data have changed.

This class can also be used for the synchronization of tables and external fillers (see class ExternalLockSync). For this purpose it is sufficient to store the number of rows.

Definition at line 78 of file TableSyncData.h.

Constructor & Destructor Documentation

casacore::TableSyncData::TableSyncData

(

)

casacore::TableSyncData::~TableSyncData

(

)

casacore::TableSyncData::TableSyncData ( const TableSyncData &  that )

private

Copy constructor is forbidden.

Member Function Documentation

uInt casacore::TableSyncData::getModifyCounter ( ) const

inline

Get the modify counter.

Definition at line 136 of file TableSyncData.h.

References itsModifyCounter.

MemoryIO & casacore::TableSyncData::memoryIO ( )

inline

Get the MemoryIO object.

This is used to let LockFile read or write the synchronization data into it.

Definition at line 132 of file TableSyncData.h.

References itsMemIO.

Referenced by casacore::ExternalLockSync::doReleaseCallBack().

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

private

Assignment is forbidden.

Bool casacore::TableSyncData::read	(	rownr_t &	nrrow,
		uInt &	nrcolumn,
		Bool &	tableChanged,
		Block< Bool > &	dataManChanged
	)

Read the synchronization data from the MemoryIO object.

This function is called when a lock is acquired to see if table data has to be reread.
It returns False when the MemoryIO object is empty.

void casacore::TableSyncData::write	(	rownr_t	nrrow,
		uInt	nrcolumn,
		Bool	tableChanged,
		const Block< Bool > &	dataManChanged
	)

Update the synchronization data and write it into the MemoryIO object.

This function is called when a table flush is done to reflect if anything has changed compared to the previous flush.

Referenced by casacore::ExternalLockSync::doReleaseCallBack().

void casacore::TableSyncData::write

(

rownr_t

nrrow

)

Update the synchronization data and write it into the MemoryIO object.

This function should be used by an external filler when it flushes its data.

Member Data Documentation

AipsIO casacore::TableSyncData::itsAipsIO

private

Definition at line 127 of file TableSyncData.h.

Block<uInt> casacore::TableSyncData::itsDataManChangeCounter

private

Definition at line 125 of file TableSyncData.h.

MemoryIO casacore::TableSyncData::itsMemIO

private

Definition at line 126 of file TableSyncData.h.

Referenced by memoryIO().

uInt casacore::TableSyncData::itsModifyCounter

private

Definition at line 123 of file TableSyncData.h.

Referenced by getModifyCounter().

Int casacore::TableSyncData::itsNrcolumn

private

Definition at line 122 of file TableSyncData.h.

rownr_t casacore::TableSyncData::itsNrrow

private

Definition at line 121 of file TableSyncData.h.

uInt casacore::TableSyncData::itsTableChangeCounter

private

Definition at line 124 of file TableSyncData.h.

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

• tables/Tables/TableSyncData.h