A generic class to read a file containing an ASDM table as a stream. More...

#include <TableStreamReader.h>

Public Member Functions
	TableStreamReader ()
	An empty constructor.
virtual	~TableStreamReader ()
	The destructor.
void	open (const std::string &directory)
	Opens a file expected to contain an ASDM table of type T with rows of type R.
void	reset ()
	Repositions the read head to the beginning of the table.
const std::vector< R * > &	nextNRows (unsigned int nRows)
	Reads at most n rows in the file, creates as many memory representations of these rows and return the reference of a vector of pointers on these representations.
const std::vector< R * > &	untilNBytes (unsigned int nBytes)
	Reads as many rows as possible in the file, keeps their in memory representation until the number of read bytes is greater or equal a number of bytes, n, passed as a parameter to the method.
bool	hasRows ()
	Returns true if the end of the file has not been reached.
void	close ()
	Releases all the resources allocated to the instance which can be reused with another file.
	TableStreamReader ()
	An empty constructor.
virtual	~TableStreamReader ()
	The destructor.
void	open (const std::string &directory)
	Opens a file expected to contain an ASDM table of type T with rows of type R.
void	reset ()
	Repositions the read head to the beginning of the table.
const std::vector< R * > &	nextNRows (unsigned int nRows)
	Reads at most n rows in the file, creates as many memory representations of these rows and return the reference of a vector of pointers on these representations.
const std::vector< R * > &	untilNBytes (unsigned int nBytes)
	Reads as many rows as possible in the file, keeps their in memory representation until the number of read bytes is greater or equal a number of bytes, n, passed as a parameter to the method.
bool	hasRows ()
	Returns true if the end of the file has not been reached.
void	close ()
	Releases all the resources allocated to the instance which can be reused with another file.
Private Types
enum	State { S_CLOSED, S_OPENED, S_CLOSED, S_OPENED }
enum	Transition { T_OPEN, T_CHECK, T_RESET, T_READ, T_CLOSE, T_OPEN, T_CHECK, T_RESET, T_READ, T_CLOSE }
enum	State { S_CLOSED, S_OPENED, S_CLOSED, S_OPENED }
enum	Transition { T_OPEN, T_CHECK, T_RESET, T_READ, T_CLOSE, T_OPEN, T_CHECK, T_RESET, T_READ, T_CLOSE }
Private Member Functions
void	checkState (Transition t, const string &methodName) const
void	clear ()
	Empty the local storage containing the rows obtained during the last read operation.
void	checkState (Transition t, const string &methodName) const
void	clear ()
	Empty the local storage containing the rows obtained during the last read operation.
Private Attributes
std::string	tablePath
std::ifstream	tableFile
off_t	fileSizeInBytes
asdm::EndianIFStream	eifs
std::vector< std::string >	attributesSeq
asdm::ASDM	asdm
std::vector< R * >	rows
char *	readBuffer
streampos	whereRowsStart
State	currentState

Detailed Description

template<class T, class R>
class asdm::TableStreamReader< T, R >

A generic class to read a file containing an ASDM table as a stream.

The purpose of this class is to provide the programmer with a way to read a file containing an ASDM table by successive slices. Each slice is transformed into the in memory representation of the rows which have been read. A slice can be specified in two ways :

a number of rows. See methods nextNRows.
a number of bytes. See methods untilNBytes.

Remarks

This class has been meant as an alternative to the historical ASDM methods getXXXX (e.g. getAntenna of getPointing) which load entirely the tables into memory.
This class allows to read a table completely independantly of the ASDM it belongs to and of the other tables of the ASDM.

Parameters:

T	The parameter T must be the type of one of the tables which can be found in an ASDM (e.g. AntennaTable)
R	The parameter R must be the type of the rows which make the content of a table of type T (e.g. AntennaRow is T is AntennaTable).

Definition at line 39 of file TableStreamReader.h.

Member Enumeration Documentation

template<class T , class R >

enum asdm::TableStreamReader::State [private]

Enumerator:

S_CLOSED
S_OPENED
S_CLOSED
S_OPENED

Definition at line 260 of file TableStreamReader.h.

template<class T , class R >

enum asdm::TableStreamReader::State [private]

Enumerator:

S_CLOSED
S_OPENED
S_CLOSED
S_OPENED

Definition at line 260 of file TableStreamReader.h.

template<class T , class R >

enum asdm::TableStreamReader::Transition [private]

Enumerator:

T_OPEN
T_CHECK
T_RESET
T_READ
T_CLOSE
T_OPEN
T_CHECK
T_RESET
T_READ
T_CLOSE

Definition at line 261 of file TableStreamReader.h.

template<class T , class R >

enum asdm::TableStreamReader::Transition [private]

Enumerator:

T_OPEN
T_CHECK
T_RESET
T_READ
T_CLOSE
T_OPEN
T_CHECK
T_RESET
T_READ
T_CLOSE

Definition at line 261 of file TableStreamReader.h.

Constructor & Destructor Documentation

template<class T , class R >

asdm::TableStreamReader< T, R >::TableStreamReader ( ) [inline]

An empty constructor.

Definition at line 44 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::currentState, asdm::TableStreamReader< T, R >::readBuffer, READBUFFERSIZE, and asdm::TableStreamReader< T, R >::S_CLOSED.

template<class T , class R >

virtual asdm::TableStreamReader< T, R >::~TableStreamReader ( ) [inline, virtual]

The destructor.

Definition at line 49 of file TableStreamReader.h.

template<class T , class R >

asdm::TableStreamReader< T, R >::TableStreamReader ( ) [inline]

An empty constructor.

Definition at line 44 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::currentState, asdm::TableStreamReader< T, R >::readBuffer, READBUFFERSIZE, and asdm::TableStreamReader< T, R >::S_CLOSED.

template<class T , class R >

virtual asdm::TableStreamReader< T, R >::~TableStreamReader ( ) [inline, virtual]

The destructor.

Definition at line 49 of file TableStreamReader.h.

Member Function Documentation

template<class T , class R >

void asdm::TableStreamReader< T, R >::checkState	(	Transition	t,
		const string &	methodName
	)		const `[inline, private]`

Definition at line 264 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::currentState, casa::name(), asdm::TableStreamReader< T, R >::S_CLOSED, asdm::TableStreamReader< T, R >::S_OPENED, asdm::TableStreamReader< T, R >::T_CHECK, asdm::TableStreamReader< T, R >::T_CLOSE, asdm::TableStreamReader< T, R >::T_OPEN, asdm::TableStreamReader< T, R >::T_READ, and asdm::TableStreamReader< T, R >::T_RESET.

Referenced by asdm::TableStreamReader< T, R >::close(), asdm::TableStreamReader< T, R >::hasRows(), asdm::TableStreamReader< T, R >::nextNRows(), asdm::TableStreamReader< T, R >::open(), asdm::TableStreamReader< T, R >::reset(), and asdm::TableStreamReader< T, R >::untilNBytes().

template<class T , class R >

void asdm::TableStreamReader< T, R >::checkState	(	Transition	t,
		const string &	methodName
	)		const `[inline, private]`

Definition at line 264 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::currentState, casa::name(), asdm::TableStreamReader< T, R >::S_CLOSED, asdm::TableStreamReader< T, R >::S_OPENED, asdm::TableStreamReader< T, R >::T_CHECK, asdm::TableStreamReader< T, R >::T_CLOSE, asdm::TableStreamReader< T, R >::T_OPEN, asdm::TableStreamReader< T, R >::T_READ, and asdm::TableStreamReader< T, R >::T_RESET.

template<class T , class R >

void asdm::TableStreamReader< T, R >::clear ( ) [inline, private]

Empty the local storage containing the rows obtained during the last read operation.

Definition at line 277 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::rows.

Referenced by asdm::TableStreamReader< T, R >::close(), asdm::TableStreamReader< T, R >::nextNRows(), asdm::TableStreamReader< T, R >::reset(), and asdm::TableStreamReader< T, R >::untilNBytes().

template<class T , class R >

void asdm::TableStreamReader< T, R >::clear ( ) [inline, private]

Empty the local storage containing the rows obtained during the last read operation.

Definition at line 277 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::rows.

template<class T , class R >

void asdm::TableStreamReader< T, R >::close ( ) [inline]

Releases all the resources allocated to the instance which can be reused with another file.

Update the state.

Definition at line 238 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::currentState, free(), asdm::TableStreamReader< T, R >::readBuffer, asdm::TableStreamReader< T, R >::S_CLOSED, asdm::TableStreamReader< T, R >::T_CLOSE, and asdm::TableStreamReader< T, R >::tableFile.

template<class T , class R >

void asdm::TableStreamReader< T, R >::close ( ) [inline]

Releases all the resources allocated to the instance which can be reused with another file.

Update the state.

Definition at line 238 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::currentState, free(), asdm::TableStreamReader< T, R >::readBuffer, asdm::TableStreamReader< T, R >::S_CLOSED, asdm::TableStreamReader< T, R >::T_CLOSE, and asdm::TableStreamReader< T, R >::tableFile.

template<class T , class R >

bool asdm::TableStreamReader< T, R >::hasRows ( ) [inline]

Returns true if the end of the file has not been reached.

Definition at line 230 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::fileSizeInBytes, asdm::TableStreamReader< T, R >::T_CHECK, and asdm::TableStreamReader< T, R >::tableFile.

Referenced by asdm::TableStreamReader< T, R >::nextNRows(), and asdm::TableStreamReader< T, R >::untilNBytes().

template<class T , class R >

bool asdm::TableStreamReader< T, R >::hasRows ( ) [inline]

Returns true if the end of the file has not been reached.

Definition at line 230 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::fileSizeInBytes, asdm::TableStreamReader< T, R >::T_CHECK, and asdm::TableStreamReader< T, R >::tableFile.

template<class T , class R >

const std::vector<R*>& asdm::TableStreamReader< T, R >::nextNRows ( unsigned int nRows ) [inline]

Reads at most n rows in the file, creates as many memory representations of these rows and return the reference of a vector of pointers on these representations.

Parameters:

nRows the maximum number of rows to read.

Returns:: a constant reference to a vector of pointers on instances of R.

Definition at line 193 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::asdm, asdm::TableStreamReader< T, R >::attributesSeq, asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::eifs, asdm::ASDM::getTable(), asdm::TableStreamReader< T, R >::hasRows(), casa::name(), asdm::TableStreamReader< T, R >::rows, and asdm::TableStreamReader< T, R >::T_READ.

template<class T , class R >

const std::vector<R*>& asdm::TableStreamReader< T, R >::nextNRows ( unsigned int nRows ) [inline]

Reads at most n rows in the file, creates as many memory representations of these rows and return the reference of a vector of pointers on these representations.

Parameters:

nRows the maximum number of rows to read.

Returns:: a constant reference to a vector of pointers on instances of R.

Definition at line 193 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::asdm, asdm::TableStreamReader< T, R >::attributesSeq, asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::eifs, asdm::ASDM::getTable(), asdm::TableStreamReader< T, R >::hasRows(), casa::name(), asdm::TableStreamReader< T, R >::rows, and asdm::TableStreamReader< T, R >::T_READ.

template<class T , class R >

void asdm::TableStreamReader< T, R >::open ( const std::string & directory ) [inline]

Opens a file expected to contain an ASDM table of type T with rows of type R.

Parameters:

directory the path to the directory containing the file.

Open the file.

streambuf * sb_p = tableFile.rdbuf()->pubsetbuf(readBuffer, READBUFFERSIZE); cout << (unsigned long long) sb_p << endl;

Determine the size of the file.

Locate the xmlPartMIMEHeader.

Locate the binaryPartMIMEHeader while accumulating the characters of the xml header.

      We have the xmlHeader , let's parse it.

Then it's an "old fashioned" MIME file for tables. Just try to deserialize it with Big_Endian for the bytes ordering.

It's a new (and correct) MIME file for tables.

       1st )  Look for a BulkStoreRef element with an attribute byteOrder.

Skip the two first children (Entity and ContainerEntity).

We found BulkStoreRef, now look for its attribute byteOrder.

        2nd) Look for the Attributes element and grab the names of the elements it contains.

Create an EndianIFStream from the substring containing the binary part.

We do nothing with that but we have to read it.

Let's read numRows but ignore it and rely on the value specified in the ASDM.xml file.

Memorize the starting point of rows.

Update the state

Definition at line 56 of file TableStreamReader.h.

template<class T , class R >

void asdm::TableStreamReader< T, R >::open ( const std::string & directory ) [inline]

Opens a file expected to contain an ASDM table of type T with rows of type R.

Parameters:

directory the path to the directory containing the file.

Open the file.

streambuf * sb_p = tableFile.rdbuf()->pubsetbuf(readBuffer, READBUFFERSIZE); cout << (unsigned long long) sb_p << endl;

Determine the size of the file.

Locate the xmlPartMIMEHeader.

Locate the binaryPartMIMEHeader while accumulating the characters of the xml header.

      We have the xmlHeader , let's parse it.

Then it's an "old fashioned" MIME file for tables. Just try to deserialize it with Big_Endian for the bytes ordering.

It's a new (and correct) MIME file for tables.

       1st )  Look for a BulkStoreRef element with an attribute byteOrder.

Skip the two first children (Entity and ContainerEntity).

We found BulkStoreRef, now look for its attribute byteOrder.

        2nd) Look for the Attributes element and grab the names of the elements it contains.

Create an EndianIFStream from the substring containing the binary part.

We do nothing with that but we have to read it.

Let's read numRows but ignore it and rely on the value specified in the ASDM.xml file.

Memorize the starting point of rows.

Update the state

Definition at line 56 of file TableStreamReader.h.

template<class T , class R >

void asdm::TableStreamReader< T, R >::reset ( ) [inline]

Repositions the read head to the beginning of the table.

The internal storage containing the result of the last read operation is cleared.

Definition at line 181 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::T_RESET, asdm::TableStreamReader< T, R >::tableFile, and asdm::TableStreamReader< T, R >::whereRowsStart.

template<class T , class R >

void asdm::TableStreamReader< T, R >::reset ( ) [inline]

Repositions the read head to the beginning of the table.

The internal storage containing the result of the last read operation is cleared.

Definition at line 181 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::T_RESET, asdm::TableStreamReader< T, R >::tableFile, and asdm::TableStreamReader< T, R >::whereRowsStart.

template<class T , class R >

const std::vector<R*>& asdm::TableStreamReader< T, R >::untilNBytes ( unsigned int nBytes ) [inline]

Reads as many rows as possible in the file, keeps their in memory representation until the number of read bytes is greater or equal a number of bytes, n, passed as a parameter to the method.

Parameters:

n	the number of read bytes which is used as an upper limit to the read operation.

Returns:: a constant reference to a vector of pointers on instances of R.

Definition at line 213 of file TableStreamReader.h.

References asdm::TableStreamReader< T, R >::asdm, asdm::TableStreamReader< T, R >::attributesSeq, asdm::TableStreamReader< T, R >::checkState(), asdm::TableStreamReader< T, R >::clear(), asdm::TableStreamReader< T, R >::eifs, asdm::ASDM::getTable(), asdm::TableStreamReader< T, R >::hasRows(), casa::name(), asdm::TableStreamReader< T, R >::rows, asdm::TableStreamReader< T, R >::T_READ, and asdm::TableStreamReader< T, R >::tableFile.

template<class T , class R >

const std::vector<R*>& asdm::TableStreamReader< T, R >::untilNBytes ( unsigned int nBytes ) [inline]

Reads as many rows as possible in the file, keeps their in memory representation until the number of read bytes is greater or equal a number of bytes, n, passed as a parameter to the method.

Parameters: