Json_path Class Reference

A JSON path expression. More...

#include <json_path.h>

Inheritance diagram for Json_path:

Public Member Functions
	Json_path (PSI_memory_key key)
	~Json_path ()
	Json_path (Json_path &&other)
	Move constructor. More...
Json_path &	operator= (Json_path &&other)
	Move assignment. More...
bool	append (const Json_path_leg &leg)
	Add a path leg to the end of this path. More...
void	clear ()
	Resets this to an empty path with no legs. More...
bool	can_match_many () const
	Return true if the path can match more than one value in a JSON document. More...
bool	to_string (String *buf) const
	Turn into a human-readable string. More...
Public Member Functions inherited from Json_seekable_path
size_t	leg_count () const
	Return the number of legs in this searchable path. More...
Json_path_iterator	begin () const
	Get an iterator pointing to the first path leg. More...
Json_path_iterator	end () const
	Get an iterator pointing just past the last path leg. More...
const Json_path_leg *	last_leg () const
	Get a pointer to the last path leg. More...

Private Attributes
MEM_ROOT	m_mem_root
	A MEM_ROOT in which the Json_path_leg objects pointed to by Json_seekable_path::m_path_legs are allocated. More...
PSI_memory_key	m_psi_key
	Key used to instrument memory usage. More...

Additional Inherited Members
Protected Member Functions inherited from Json_seekable_path
	Json_seekable_path (PSI_memory_key key)
Protected Attributes inherited from Json_seekable_path
Json_path_leg_pointers	m_path_legs
	An array of pointers to the legs of the JSON path. More...

Detailed Description

A JSON path expression.

From the user's point of view, a path expression is a string literal with the following structure. We parse this structure into a Json_path object:

pathExpression ::= scope  pathLeg (pathLeg)*

scope ::= dollarSign

pathLeg ::= member | arrayLocation | doubleAsterisk

member ::= period (keyName | asterisk)

arrayLocation ::=
  leftBracket
    (arrayIndex | arrayRange | asterisk)
  rightBracket

arrayIndex ::=
  non-negative-integer |
  last [ minus non-negative-integer ]

arrayRange ::= arrayIndex to arrayIndex

keyName ::= ECMAScript-identifier | ECMAScript-string-literal

doubleAsterisk ::= **

to ::= "to"

last ::= "last"

Constructor & Destructor Documentation

Json_path() [1/2]

Json_path::Json_path ( PSI_memory_key  key )

explicit

~Json_path()

Json_path::~Json_path ( )

inline

Json_path() [2/2]

Json_path::Json_path ( Json_path &&  other )

inline

Move constructor.

Member Function Documentation

append()

bool Json_path::append ( const Json_path_leg &  leg )

inline

Add a path leg to the end of this path.

Parameters

[in]

leg

the leg to add

Returns

false on success, true on error

can_match_many()

bool Json_path::can_match_many

(

)

const

Return true if the path can match more than one value in a JSON document.

Return values

true	if the path contains a path leg which is a wildcard, ellipsis or array range
false	otherwise

clear()

void Json_path::clear ( )

inline

Resets this to an empty path with no legs.

operator=()

Json_path & Json_path::operator= ( Json_path &&  other )

inline

Move assignment.

to_string()

bool Json_path::to_string

(

String *

buf

)

const

Turn into a human-readable string.

Member Data Documentation

m_mem_root

MEM_ROOT Json_path::m_mem_root

private

A MEM_ROOT in which the Json_path_leg objects pointed to by Json_seekable_path::m_path_legs are allocated.

m_psi_key

PSI_memory_key Json_path::m_psi_key

private

Key used to instrument memory usage.

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

• sql-common/json_path.h
• sql-common/json_path.cc