impala::StringBuffer Class Reference

#include <string-buffer.h>

Collaboration diagram for impala::StringBuffer:

Public Member Functions
	StringBuffer (MemPool *pool, StringValue *str=NULL)
void	Append (const char *str, int len)
	Append 'str' to the current string, allocating a new buffer as necessary. More...
void	Append (const uint8_t *str, int len)
	TODO: switch everything to uint8_t? More...
void	Assign (const char *str, int len)
	Assigns contents to StringBuffer. More...
void	Clear ()
	Clear the underlying StringValue. The allocated buffer can be reused. More...
void	Reset ()
	Clears the underlying buffer and StringValue. More...
bool	Empty () const
	Returns whether the current string is empty. More...
int	Size () const
	Returns the length of the current string. More...
const StringValue &	str () const
	Returns the underlying StringValue. More...
int	buffer_size () const
	Returns the buffer size. More...

Private Member Functions
void	GrowBuffer (int new_len)

Private Attributes
MemPool *	pool_
StringValue	string_value_
int	buffer_size_

Detailed Description

Dynamic-sizable string (similar to std::string) but without as many copies and allocations. StringBuffer wraps a StringValue object with a pool and memory buffer length. It supports a subset of the std::string functionality but will only allocate bigger string buffers as necessary. std::string tries to be immutable and will reallocate very often. std::string should be avoided in all hot paths.

Definition at line 30 of file string-buffer.h.

Constructor & Destructor Documentation

impala::StringBuffer::StringBuffer ( MemPool *  pool, StringValue *  str = NULL  )

inline

C'tor for StringBuffer. Memory backing the string will be allocated from the pool as necessary. Can optionally be initialized from a StringValue.

Definition at line 34 of file string-buffer.h.

References buffer_size_, impala::StringValue::len, pool_, str(), and string_value_.

Member Function Documentation

void impala::StringBuffer::Append ( const char *  str, int  len  )

inline

Append 'str' to the current string, allocating a new buffer as necessary.

Definition at line 44 of file string-buffer.h.

References buffer_size_, GrowBuffer(), impala::StringValue::len, impala::StringValue::ptr, and string_value_.

Referenced by Append(), Assign(), impala::HdfsTextScanner::ProcessRange(), and impala::TEST().

void impala::StringBuffer::Append ( const uint8_t *  str, int  len  )

inline

TODO: switch everything to uint8_t?

Definition at line 54 of file string-buffer.h.

References Append().

void impala::StringBuffer::Assign ( const char *  str, int  len  )

inline

Assigns contents to StringBuffer.

Definition at line 59 of file string-buffer.h.

References Append(), and Clear().

Referenced by impala::TEST().

int impala::StringBuffer::buffer_size ( ) const

inline

Returns the buffer size.

Definition at line 91 of file string-buffer.h.

References buffer_size_.

Referenced by impala::TEST().

void impala::StringBuffer::Clear ( )

inline

Clear the underlying StringValue. The allocated buffer can be reused.

Definition at line 65 of file string-buffer.h.

References impala::StringValue::len, and string_value_.

Referenced by Assign(), impala::HdfsTextScanner::ProcessRange(), impala::HdfsTextScanner::ResetScanner(), impala::TEST(), and impala::HdfsTextScanner::WriteFields().

bool impala::StringBuffer::Empty ( ) const

inline

Returns whether the current string is empty.

Definition at line 76 of file string-buffer.h.

References impala::StringValue::len, and string_value_.

Referenced by impala::HdfsTextScanner::FinishScanRange(), impala::HdfsTextScanner::LogRowParseError(), impala::HdfsTextScanner::ProcessRange(), and impala::ValidateString().

void impala::StringBuffer::GrowBuffer ( int  new_len )

inlineprivate

Grows the buffer backing the string to be at least new_size, copying over the previous string data into the new buffer.

Definition at line 98 of file string-buffer.h.

References impala::MemPool::Allocate(), buffer_size_, impala::StringValue::len, pool_, impala::StringValue::ptr, and string_value_.

Referenced by Append().

void impala::StringBuffer::Reset ( )

inline

Clears the underlying buffer and StringValue.

Definition at line 70 of file string-buffer.h.

References buffer_size_, impala::StringValue::len, and string_value_.

int impala::StringBuffer::Size ( ) const

inline

Returns the length of the current string.

Definition at line 81 of file string-buffer.h.

References impala::StringValue::len, and string_value_.

Referenced by impala::HdfsTextScanner::CopyBoundaryField(), impala::HdfsTextScanner::FinishScanRange(), and impala::ValidateString().

const StringValue& impala::StringBuffer::str ( ) const

inline

Returns the underlying StringValue.

Definition at line 86 of file string-buffer.h.

References string_value_.

Referenced by impala::HdfsTextScanner::CopyBoundaryField(), impala::HdfsTextScanner::FinishScanRange(), impala::HdfsTextScanner::LogRowParseError(), StringBuffer(), and impala::ValidateString().

Member Data Documentation

int impala::StringBuffer::buffer_size_

private

Definition at line 110 of file string-buffer.h.

Referenced by Append(), buffer_size(), GrowBuffer(), Reset(), and StringBuffer().

MemPool* impala::StringBuffer::pool_

private

Definition at line 108 of file string-buffer.h.

Referenced by GrowBuffer(), and StringBuffer().

StringValue impala::StringBuffer::string_value_

private

Definition at line 109 of file string-buffer.h.

Referenced by Append(), Clear(), Empty(), GrowBuffer(), Reset(), Size(), str(), and StringBuffer().

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

• be/src/runtime/string-buffer.h