General Reader that provides functions for reading tuples. More...

#include <reader.h>

Inheritance diagram for singa::io::Reader:

Public Member Functions
virtual	~Reader ()
	In case that users forget to call Close() to release resources, e.g., memory, you can release them here. More...

virtual bool	Open (const std::string &path)=0
	path is the path to the storage, could be a file path, database connection, or hdfs path. More...

virtual void	Close ()=0
	Release resources.

virtual bool	Read (std::string key, std::string value)=0
	Read a tuple. More...

virtual int	Count ()=0
	Iterate through all tuples to get the num of all tuples. More...

virtual void	SeekToFirst ()=0
	Seek to the first tuple when the cursor arrives to the end of the file.

Detailed Description

General Reader that provides functions for reading tuples.

Subclasses implement the functions for a specific data storage, e.g., CSV file, HDFS, kvfile, leveldb, lmdb, etc.

Constructor & Destructor Documentation

virtual singa::io::Reader::~Reader ( )

inlinevirtual

In case that users forget to call Close() to release resources, e.g., memory, you can release them here.

virtual int singa::io::Reader::Count ( )

pure virtual

Iterate through all tuples to get the num of all tuples.

return num of tuples

virtual bool singa::io::Reader::Open ( const std::string & path )

pure virtual

path is the path to the storage, could be a file path, database connection, or hdfs path.

return true if open successfully, otherwise false.

virtual bool singa::io::Reader::Read	(	std::string *	key,
		std::string *	value
	)

pure virtual

Read a tuple.

return true if read successfully; return flase if coming to the end of the file; LOG(FATAL) if error happens.

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