evio::EvioCompactReaderV4 Class Reference

This class is used to read an evio format version 4 formatted file or buffer and extract specific evio containers (bank, seg, or tagseg) with actual data in them given a tag/num pair. More...

#include <EvioCompactReaderV4.h>

Public Member Functions
	EvioCompactReaderV4 (std::string const &path)
	Constructor for reading an event file. More...
	EvioCompactReaderV4 (std::shared_ptr< ByteBuffer > &byteBuffer)
	Constructor for reading a buffer. More...
void	setBuffer (std::shared_ptr< ByteBuffer > &buf) override
	This method can be used to avoid creating additional EvioCompactReader objects by reusing this one with another buffer.The method close() should be called before calling this. Parameters buf ByteBuffer to be read Exceptions EvioException if arg is null; if failure to read first block header; if buffer not in evio format. More...
bool	isFile () override
	Is this reader reading a file? Returns true if reading file, false if reading buffer More...
bool	isCompressed () override
	Is the data in the file/buffer compressed? Returns true if data is compressed. More...
bool	isClosed () override
	Has close() been called (without reopening by calling setBuffer(std::shared_ptr<ByteBuffer> &))? Returns true if this object closed, else false . More...
ByteOrder	getByteOrder () override
	Get the byte order of the file/buffer being read. Returns byte order of the file/buffer being read. More...
uint32_t	getEvioVersion () override
	Get the evio version number. Returns evio version number. More...
std::string	getPath () override
	Get the path to the file. Returns path to the file More...
ByteOrder	getFileByteOrder () override
	When reading a file, this method's return value is the byte order of the evio data in the file. Returns byte order of the evio data in the file. More...
std::string	getDictionaryXML () override
	Get the XML format dictionary is there is one. Exceptions EvioException if object closed and dictionary still unread Returns XML format dictionary, else null. More...
std::shared_ptr < EvioXMLDictionary >	getDictionary () override
	Get the evio dictionary if is there is one. Exceptions EvioException if object closed and dictionary still unread Returns evio dictionary if exists, else null. More...
bool	hasDictionary () override
	Does this evio file have an associated XML dictionary? Returns true if this evio file has an associated XML dictionary, else false More...
std::shared_ptr< ByteBuffer >	getByteBuffer () override
	Get the byte buffer being read directly or corresponding to the event file. Returns the byte buffer being read directly or corresponding to the event file. More...
size_t	fileSize () override
	Get the size of the file being read, in bytes.For small files, obtain the file size using the memory mapped buffer's capacity. Returns the file size in bytes More...
std::shared_ptr< EvioNode >	getEvent (size_t eventNumber) override
	Get the EvioNode object associated with a particular event number. Parameters eventNumber number of event (place in file/buffer) starting at 1. Returns EvioNode object associated with a particular event number, or null if there is none. More...
std::shared_ptr< EvioNode >	getScannedEvent (size_t eventNumber) override
	Get the EvioNode object associated with a particular event number which has been scanned so all substructures are contained in the node.allNodes list. Parameters eventNumber number of event (place in file/buffer) starting at 1. Returns EvioNode object associated with a particular event number, or null if there is none. More...
std::shared_ptr< IBlockHeader >	getFirstBlockHeader () override
	This returns the FIRST block (or record) header.(Not the file header of evio version 6+ files). Returns the first block header. More...
void	searchEvent (size_t eventNumber, uint16_t tag, uint8_t num, std::vector< std::shared_ptr< EvioNode >> &vec) override
	This method searches the specified event in a file/buffer and returns a vector of objects each of which contain information about a single evio structure which matches the given tag and num. Parameters eventNumber place of event in buffer (starting with 1) tag tag to match. num num to match. vec vector to be filled with matching evio structures (empty if none found). Exceptions EvioException if bad arg value(s); if object closed More...
void	searchEvent (size_t eventNumber, std::string const &dictName, std::shared_ptr< EvioXMLDictionary > &dictionary, std::vector< std::shared_ptr< EvioNode >> &vec) override
	This method searches the specified event in a file/buffer and returns a vector of objects each of which contain information about a single evio structure which matches the given dictionary entry name. Parameters eventNumber place of event in buffer (starting with 1) dictName name of dictionary entry to search for dictionary dictionary to use; if null, use dictionary with file/buffer vec vector to be filled with matching evio structures (empty if none found). Exceptions EvioException if dictName is null; if dictName is an invalid dictionary entry; if dictionary is null and none provided in file/buffer being read; if object closed More...
std::shared_ptr< ByteBuffer >	removeEvent (size_t eventNumber) override
	This method removes the data of the given event from the buffer.It also marks any existing EvioNodes representing the event and its descendants as obsolete. They must not be used anymore.If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not change the file originally used. A new file can be created by calling either the toFile(std::string const &) method. Parameters eventNumber number of event to remove from buffer Returns new ByteBuffer created and updated to reflect the event removal Exceptions EvioException if evNumber < 1; if event number does not correspond to existing event; if object closed; if node was not found in any event; if internal programming error More...
std::shared_ptr< ByteBuffer >	removeStructure (std::shared_ptr< EvioNode > &removeNode) override
	This method removes the data, represented by the given node, from the buffer.It also marks the node and its descendants as obsolete. They must not be used anymore.If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not change the file originally used. A new file can be created by calling either the toFile(std::string const &) method. Parameters removeNode evio structure to remove from buffer Returns new ByteBuffer (perhaps created) and updated to reflect the node removal Exceptions EvioException if object closed; if node was not found in any event; if internal programming error More...
std::shared_ptr< ByteBuffer >	addStructure (size_t eventNumber, ByteBuffer &addBuffer) override
	This method adds an evio container (bank, segment, or tag segment) as the last structure contained in an event.It is the responsibility of the caller to make sure that the buffer argument contains valid evio data (only data representing the structure to be added - not in file format with block header and the like) which is compatible with the type of data stored in the given event.To produce such evio data use EvioBank#write(ByteBuffer &), EvioSegment#write(ByteBuffer &) or EvioTagSegment#write(ByteBuffer &) depending on whether a bank, seg, or tagseg is being added.A note about files here. If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not expand the file originally used. A new file can be created by calling either the toFile(std::string const &) method.The given buffer argument must be ready to read with its position and limit defining the limits of the data to copy. This method is synchronized due to the bulk, relative puts. Parameters eventNumber number of event to which addBuffer is to be added addBuffer buffer containing evio data to add (not evio file format, i.e. no block headers) Returns a new ByteBuffer object which is created and filled with all the data including what was just added. Exceptions EvioException if evNumber < 1; if addBuffer is null; if addBuffer arg is empty or has non-evio format; if addBuffer is opposite endian to current event buffer; if added data is not the proper length (i.e. multiple of 4 bytes); if the event number does not correspond to an existing event; if there is an internal programming error; if object closed More...
std::shared_ptr< ByteBuffer >	getData (std::shared_ptr< EvioNode > &node) override
	Get the data associated with an evio structure in ByteBuffer form.The returned buffer is a view into this reader's buffer (no copy done). Changes in one will affect the other. Parameters node evio structure whose data is to be retrieved Exceptions EvioException if object closed or node arg is null. Returns ByteBuffer filled with data. More...
std::shared_ptr< ByteBuffer >	getData (std::shared_ptr< EvioNode > &node, bool copy) override
	Get the data associated with an evio structure in ByteBuffer form.Depending on the copy argument, the given/returned buffer will either be a copy of or a view into the data of this reader's buffer.This method is synchronized due to the bulk, relative gets & puts. Parameters node evio structure whose data is to be retrieved copy if true, then return a copy as opposed to a view into this reader object's buffer. Exceptions EvioException if object closed Returns ByteBuffer filled with data. More...
std::shared_ptr< ByteBuffer >	getData (std::shared_ptr< EvioNode > &node, std::shared_ptr< ByteBuffer > &buf) override
	Get the data associated with an evio structure in ByteBuffer form.The returned buffer is a view into this reader's buffer (no copy done). Changes in one will affect the other. Parameters node evio structure whose data is to be retrieved buf user-supplied ByteBuffer to be filled with data. Exceptions EvioException if object closed or node arg is null. Returns buf arg. More...
std::shared_ptr< ByteBuffer >	getData (std::shared_ptr< EvioNode > &node, std::shared_ptr< ByteBuffer > &buf, bool copy) override
	Get the data associated with an evio structure in ByteBuffer form.Depending on the copy argument, the given/returned buffer will either be a copy of or a view into the data of this reader's buffer.This method is synchronized due to the bulk, relative gets & puts. Parameters node evio structure whose data is to be retrieved buf user-supplied ByteBuffer to be filled with data. copy if true, then return a copy as opposed to a view into this reader object's buffer. Exceptions EvioException if object closed Returns buf arg. More...
std::shared_ptr< ByteBuffer >	getEventBuffer (size_t eventNumber) override
	Get an evio bank or event in ByteBuffer form.The returned buffer is a view into the data of this reader's buffer. Parameters eventNumber number of event of interest Returns ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading. Exceptions EvioException if evNumber < 1; if the event number does not correspond to an existing event; if object closed More...
std::shared_ptr< ByteBuffer >	getEventBuffer (size_t eventNumber, bool copy) override
	Get an evio bank or event in ByteBuffer form.Depending on the copy argument, the returned buffer will either be a copy of or a view into the data of this reader's buffer. Parameters eventNumber number of event of interest copy if true, then return a copy as opposed to a view into this reader object's buffer. Returns ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading. Exceptions EvioException if evNumber < 1; if the event number does not correspond to an existing event; if object closed More...
std::shared_ptr< ByteBuffer >	getStructureBuffer (std::shared_ptr< EvioNode > &node) override
	Get an evio structure (bank, seg, or tagseg) in ByteBuffer form.The returned buffer is a view into the data of this reader's buffer. Parameters node node object representing evio structure of interest Returns ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading. Exceptions EvioException if node is null; if object closed More...
std::shared_ptr< ByteBuffer >	getStructureBuffer (std::shared_ptr< EvioNode > &node, bool copy) override
	Get an evio structure (bank, seg, or tagseg) in ByteBuffer form.Depending on the copy argument, the returned buffer will either be a copy of or a view into the data of this reader's buffer. Parameters node node object representing evio structure of interest copy if true, then return a copy as opposed to a view into this reader object's buffer. Returns ByteBuffer object containing structure's bytes. Position and limit are set for reading. Exceptions EvioException if node is null; if object closed More...
void	close () override
	This only sets the position to its initial value. More...
uint32_t	getEventCount () override
	This is the number of events in the file/buffer.Any dictionary event is not included in the count. In versions 3 and earlier, it is not computed unless asked for, and if asked for it is computed and cached. Returns the number of events in the file/buffer. More...
uint32_t	getBlockCount () override
	This is the number of blocks in the file/buffer including the empty block at the end. Returns the number of blocks in the file/buffer (estimate for version 3 files) More...
void	toFile (std::string const &fileName) override
	Save the internal byte buffer to the given file (overwrites existing file). Parameters fileName name of file to write Exceptions IOException if error writing to file EvioException if fileName arg is null; if object closed More...

Static Public Attributes
static const int	BLOCK_SIZE_OFFSET = 0
	Offset to get block size from start of block. More...
static const int	BLOCK_NUMBER = 4
	Offset to get block number from start of block. More...
static const int	BLOCK_HEADER_SIZE_OFFSET = 8
	Offset to get block header size from start of block. More...
static const int	BLOCK_EVENT_COUNT = 12
	Offset to get block event count from start of block. More...
static const int	BLOCK_RESERVED_1 = 16
	Offset to get block size from start of block. More...
static const int	VERSION_MASK = 0xff
	Mask to get version number from 6th int in block. More...

Detailed Description

This class is used to read an evio format version 4 formatted file or buffer and extract specific evio containers (bank, seg, or tagseg) with actual data in them given a tag/num pair.

Date

07/01/2020

Author

timmer

Constructor & Destructor Documentation

evio::EvioCompactReaderV4::EvioCompactReaderV4 ( std::string const &  path )

explicit

Constructor for reading an event file.

Parameters

path	the full path to the file that contains events. For writing event files, use an EventWriter object.

See Also

EventWriter

Exceptions

EvioException

if read failure, if path arg is empty

Object for reading file.

evio::EvioCompactReaderV4::EvioCompactReaderV4 ( std::shared_ptr< ByteBuffer > &  byteBuffer )

explicit

Constructor for reading a buffer.

Parameters

byteBuffer

the buffer that contains events.

See Also

EventWriter

Exceptions

EvioException

if buffer arg is null; failure to read first block header

Member Function Documentation

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::addStructure ( size_t  eventNumber, ByteBuffer &  addBuffer  )

overridevirtual

This method adds an evio container (bank, segment, or tag segment) as the last structure contained in an event.It is the responsibility of the caller to make sure that the buffer argument contains valid evio data (only data representing the structure to be added - not in file format with block header and the like) which is compatible with the type of data stored in the given event.To produce such evio data use EvioBank#write(ByteBuffer &), EvioSegment#write(ByteBuffer &) or EvioTagSegment#write(ByteBuffer &) depending on whether a bank, seg, or tagseg is being added.A note about files here. If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not expand the file originally used. A new file can be created by calling either the toFile(std::string const &) method.The given buffer argument must be ready to read with its position and limit defining the limits of the data to copy. This method is synchronized due to the bulk, relative puts.

Parameters

eventNumber	number of event to which addBuffer is to be added
addBuffer	buffer containing evio data to add (not evio file format, i.e. no block headers)

Returns

a new ByteBuffer object which is created and filled with all the data including what was just added.

Exceptions

EvioException

if evNumber < 1; if addBuffer is null; if addBuffer arg is empty or has non-evio format; if addBuffer is opposite endian to current event buffer; if added data is not the proper length (i.e. multiple of 4 bytes); if the event number does not correspond to an existing event; if there is an internal programming error; if object closed

Implements evio::IEvioCompactReader.

References evio::DataType::ALSOBANK, evio::DataType::ALSOSEGMENT, evio::DataType::BANK, evio::ByteOrder::ENDIAN_BIG, evio::EvioNode::extractNode(), evio::ByteBuffer::order(), evio::ByteBuffer::position(), evio::ByteBuffer::remaining(), evio::EvioNode::scanStructure(), evio::DataType::SEGMENT, and evio::DataType::TAGSEGMENT.

void evio::EvioCompactReaderV4::close ( )

overridevirtual

This only sets the position to its initial value.

Implements evio::IEvioCompactReader.

size_t evio::EvioCompactReaderV4::fileSize ( )

overridevirtual

Get the size of the file being read, in bytes.For small files, obtain the file size using the memory mapped buffer's capacity.

Returns

the file size in bytes

Implements evio::IEvioCompactReader.

uint32_t evio::EvioCompactReaderV4::getBlockCount ( )

overridevirtual

This is the number of blocks in the file/buffer including the empty block at the end.

Returns

the number of blocks in the file/buffer (estimate for version 3 files)

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getByteBuffer ( )

overridevirtual

Get the byte buffer being read directly or corresponding to the event file.

Returns

the byte buffer being read directly or corresponding to the event file.

Implements evio::IEvioCompactReader.

ByteOrder evio::EvioCompactReaderV4::getByteOrder ( )

overridevirtual

Get the byte order of the file/buffer being read.

Returns

byte order of the file/buffer being read.

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getData ( std::shared_ptr< EvioNode > &  node )

overridevirtual

Get the data associated with an evio structure in ByteBuffer form.The returned buffer is a view into this reader's buffer (no copy done). Changes in one will affect the other.

Parameters

node	evio structure whose data is to be retrieved

Exceptions

EvioException

if object closed or node arg is null.

Returns

ByteBuffer filled with data.

Implements evio::IEvioCompactReader.

Referenced by getData().

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getData ( std::shared_ptr< EvioNode > &  node, bool  copy  )

overridevirtual

Get the data associated with an evio structure in ByteBuffer form.Depending on the copy argument, the given/returned buffer will either be a copy of or a view into the data of this reader's buffer.This method is synchronized due to the bulk, relative gets & puts.

Parameters

node	evio structure whose data is to be retrieved
copy	if true, then return a copy as opposed to a view into this reader object's buffer.

Exceptions

EvioException

if object closed

Returns

ByteBuffer filled with data.

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getData ( std::shared_ptr< EvioNode > &  node, std::shared_ptr< ByteBuffer > &  buf  )

overridevirtual

Get the data associated with an evio structure in ByteBuffer form.The returned buffer is a view into this reader's buffer (no copy done). Changes in one will affect the other.

Parameters

node	evio structure whose data is to be retrieved
buf	user-supplied ByteBuffer to be filled with data.

Exceptions

EvioException

if object closed or node arg is null.

Returns

buf arg.

Implements evio::IEvioCompactReader.

References getData().

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getData ( std::shared_ptr< EvioNode > &  node, std::shared_ptr< ByteBuffer > &  buf, bool  copy  )

overridevirtual

Get the data associated with an evio structure in ByteBuffer form.Depending on the copy argument, the given/returned buffer will either be a copy of or a view into the data of this reader's buffer.This method is synchronized due to the bulk, relative gets & puts.

Parameters

node	evio structure whose data is to be retrieved
buf	user-supplied ByteBuffer to be filled with data.
copy	if true, then return a copy as opposed to a view into this reader object's buffer.

Exceptions

EvioException

if object closed

Returns

buf arg.

Implements evio::IEvioCompactReader.

std::shared_ptr< EvioXMLDictionary > evio::EvioCompactReaderV4::getDictionary ( )

overridevirtual

Get the evio dictionary if is there is one.

Exceptions

EvioException

if object closed and dictionary still unread

Returns

evio dictionary if exists, else null.

Implements evio::IEvioCompactReader.

Referenced by searchEvent().

std::string evio::EvioCompactReaderV4::getDictionaryXML ( )

overridevirtual

Get the XML format dictionary is there is one.

Exceptions

EvioException

if object closed and dictionary still unread

Returns

XML format dictionary, else null.

Implements evio::IEvioCompactReader.

std::shared_ptr< EvioNode > evio::EvioCompactReaderV4::getEvent ( size_t  eventNumber )

overridevirtual

Get the EvioNode object associated with a particular event number.

Parameters

eventNumber

number of event (place in file/buffer) starting at 1.

Returns

EvioNode object associated with a particular event number, or null if there is none.

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getEventBuffer ( size_t  eventNumber )

overridevirtual

Get an evio bank or event in ByteBuffer form.The returned buffer is a view into the data of this reader's buffer.

Parameters

eventNumber

number of event of interest

Returns

ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading.

Exceptions

EvioException

if evNumber < 1; if the event number does not correspond to an existing event; if object closed

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getEventBuffer ( size_t  eventNumber, bool  copy  )

overridevirtual

Get an evio bank or event in ByteBuffer form.Depending on the copy argument, the returned buffer will either be a copy of or a view into the data of this reader's buffer.

Parameters

eventNumber	number of event of interest
copy	if true, then return a copy as opposed to a view into this reader object's buffer.

Returns

ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading.

Exceptions

EvioException

if evNumber < 1; if the event number does not correspond to an existing event; if object closed

Implements evio::IEvioCompactReader.

uint32_t evio::EvioCompactReaderV4::getEventCount ( )

overridevirtual

This is the number of events in the file/buffer.Any dictionary event is not included in the count. In versions 3 and earlier, it is not computed unless asked for, and if asked for it is computed and cached.

Returns

the number of events in the file/buffer.

Implements evio::IEvioCompactReader.

uint32_t evio::EvioCompactReaderV4::getEvioVersion ( )

overridevirtual

Get the evio version number.

Returns

evio version number.

Implements evio::IEvioCompactReader.

ByteOrder evio::EvioCompactReaderV4::getFileByteOrder ( )

overridevirtual

When reading a file, this method's return value is the byte order of the evio data in the file.

Returns

byte order of the evio data in the file.

Implements evio::IEvioCompactReader.

std::shared_ptr< IBlockHeader > evio::EvioCompactReaderV4::getFirstBlockHeader ( )

overridevirtual

This returns the FIRST block (or record) header.(Not the file header of evio version 6+ files).

Returns

the first block header.

Implements evio::IEvioCompactReader.

std::string evio::EvioCompactReaderV4::getPath ( )

overridevirtual

Get the path to the file.

Returns

path to the file

Implements evio::IEvioCompactReader.

std::shared_ptr< EvioNode > evio::EvioCompactReaderV4::getScannedEvent ( size_t  eventNumber )

overridevirtual

Get the EvioNode object associated with a particular event number which has been scanned so all substructures are contained in the node.allNodes list.

Parameters

eventNumber

number of event (place in file/buffer) starting at 1.

Returns

EvioNode object associated with a particular event number, or null if there is none.

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getStructureBuffer ( std::shared_ptr< EvioNode > &  node )

overridevirtual

Get an evio structure (bank, seg, or tagseg) in ByteBuffer form.The returned buffer is a view into the data of this reader's buffer.

Parameters

node	node object representing evio structure of interest

Returns

ByteBuffer object containing bank's/event's bytes. Position and limit are set for reading.

Exceptions

EvioException

if node is null; if object closed

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::getStructureBuffer ( std::shared_ptr< EvioNode > &  node, bool  copy  )

overridevirtual

Get an evio structure (bank, seg, or tagseg) in ByteBuffer form.Depending on the copy argument, the returned buffer will either be a copy of or a view into the data of this reader's buffer.

Parameters

node	node object representing evio structure of interest
copy	if true, then return a copy as opposed to a view into this reader object's buffer.

Returns

ByteBuffer object containing structure's bytes. Position and limit are set for reading.

Exceptions

EvioException

if node is null; if object closed

Implements evio::IEvioCompactReader.

bool evio::EvioCompactReaderV4::hasDictionary ( )

overridevirtual

Does this evio file have an associated XML dictionary?

Returns

true if this evio file has an associated XML dictionary, else false

Implements evio::IEvioCompactReader.

Referenced by searchEvent().

bool evio::EvioCompactReaderV4::isClosed ( )

overridevirtual

Has close() been called (without reopening by calling setBuffer(std::shared_ptr<ByteBuffer> &))?

Returns

true 

if this object closed, else

false 

.

Implements evio::IEvioCompactReader.

bool evio::EvioCompactReaderV4::isCompressed ( )

overridevirtual

Is the data in the file/buffer compressed?

Returns

true if data is compressed.

Implements evio::IEvioCompactReader.

bool evio::EvioCompactReaderV4::isFile ( )

overridevirtual

Is this reader reading a file?

Returns

true if reading file, false if reading buffer

Implements evio::IEvioCompactReader.

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::removeEvent ( size_t  eventNumber )

overridevirtual

This method removes the data of the given event from the buffer.It also marks any existing EvioNodes representing the event and its descendants as obsolete. They must not be used anymore.If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not change the file originally used. A new file can be created by calling either the toFile(std::string const &) method.

Parameters

eventNumber

number of event to remove from buffer

Returns

new ByteBuffer created and updated to reflect the event removal

Exceptions

EvioException

if evNumber < 1; if event number does not correspond to existing event; if object closed; if node was not found in any event; if internal programming error

Implements evio::IEvioCompactReader.

References removeStructure().

std::shared_ptr< ByteBuffer > evio::EvioCompactReaderV4::removeStructure ( std::shared_ptr< EvioNode > &  removeNode )

overridevirtual

This method removes the data, represented by the given node, from the buffer.It also marks the node and its descendants as obsolete. They must not be used anymore.If the constructor of this reader read in data from a file, it will now switch to using a new, internal buffer which is returned by this method or can be retrieved by calling getByteBuffer(). It will not change the file originally used. A new file can be created by calling either the toFile(std::string const &) method.

Parameters

removeNode

evio structure to remove from buffer

Returns

new ByteBuffer (perhaps created) and updated to reflect the node removal

Exceptions

EvioException

if object closed; if node was not found in any event; if internal programming error

Implements evio::IEvioCompactReader.

References evio::DataType::ALSOBANK, evio::DataType::ALSOSEGMENT, evio::DataType::BANK, evio::ByteOrder::ENDIAN_BIG, evio::DataType::SEGMENT, and evio::DataType::TAGSEGMENT.

Referenced by removeEvent().

void evio::EvioCompactReaderV4::searchEvent ( size_t  eventNumber, uint16_t  tag, uint8_t  num, std::vector< std::shared_ptr< EvioNode >> &  vec  )

overridevirtual

This method searches the specified event in a file/buffer and returns a vector of objects each of which contain information about a single evio structure which matches the given tag and num.

Parameters

eventNumber	place of event in buffer (starting with 1)
tag	tag to match.
num	num to match.
vec	vector to be filled with matching evio structures (empty if none found).

Exceptions

EvioException

if bad arg value(s); if object closed

Implements evio::IEvioCompactReader.

Referenced by searchEvent().

void evio::EvioCompactReaderV4::searchEvent ( size_t  eventNumber, std::string const &  dictName, std::shared_ptr< EvioXMLDictionary > &  dictionary, std::vector< std::shared_ptr< EvioNode >> &  vec  )

overridevirtual

This method searches the specified event in a file/buffer and returns a vector of objects each of which contain information about a single evio structure which matches the given dictionary entry name.

Parameters

eventNumber	place of event in buffer (starting with 1)
dictName	name of dictionary entry to search for
dictionary	dictionary to use; if null, use dictionary with file/buffer
vec	vector to be filled with matching evio structures (empty if none found).

Exceptions

EvioException

if dictName is null; if dictName is an invalid dictionary entry; if dictionary is null and none provided in file/buffer being read; if object closed

Implements evio::IEvioCompactReader.

References getDictionary(), hasDictionary(), and searchEvent().

void evio::EvioCompactReaderV4::setBuffer ( std::shared_ptr< ByteBuffer > &  buf )

overridevirtual

This method can be used to avoid creating additional EvioCompactReader objects by reusing this one with another buffer.The method close() should be called before calling this.

Parameters

buf	ByteBuffer to be read

Exceptions

EvioException

if arg is null; if failure to read first block header; if buffer not in evio format.

Implements evio::IEvioCompactReader.

void evio::EvioCompactReaderV4::toFile ( std::string const &  fileName )

overridevirtual

Save the internal byte buffer to the given file (overwrites existing file).

Parameters

fileName

name of file to write

Exceptions

IOException	if error writing to file
EvioException	if fileName arg is null; if object closed

Implements evio::IEvioCompactReader.

Member Data Documentation

const int evio::EvioCompactReaderV4::BLOCK_EVENT_COUNT = 12

static

Offset to get block event count from start of block.

const int evio::EvioCompactReaderV4::BLOCK_HEADER_SIZE_OFFSET = 8

static

Offset to get block header size from start of block.

const int evio::EvioCompactReaderV4::BLOCK_NUMBER = 4

static

Offset to get block number from start of block.

const int evio::EvioCompactReaderV4::BLOCK_RESERVED_1 = 16

static

Offset to get block size from start of block.

const int evio::EvioCompactReaderV4::BLOCK_SIZE_OFFSET = 0

static

Offset to get block size from start of block.

const int evio::EvioCompactReaderV4::VERSION_MASK = 0xff

static

Mask to get version number from 6th int in block.

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

• EvioCompactReaderV4.h
• EvioCompactReaderV4.cpp