Represents a JSON container value of type "object" (ECMA), type J_OBJECT here. More...

#include <json_dom.h>

Inheritance diagram for Json_object:

Public Types
typedef Json_object_map::const_iterator	const_iterator
	Constant iterator over the elements in the JSON object. More...

Public Member Functions
	Json_object ()

enum_json_type	json_type () const override

bool	add_clone (const std::string &key, const Json_dom *value)
	Insert a clone of the value into the object. More...

bool	add_alias (const std::string &key, Json_dom *value)
	Insert the value into the object. More...

bool	add_alias (const std::string &key, Json_dom_ptr value)
	Insert the value into the object. More...

bool	consume (Json_object_ptr other)
	Transfer all of the key/value pairs in the other object into this object. More...

Json_dom *	get (const std::string &key) const
	Return the value at key. More...

Json_dom *	get (const MYSQL_LEX_CSTRING &key) const

bool	remove (const std::string &key)
	Remove the child element addressed by key. More...

size_t	cardinality () const

uint32	depth () const override
	Compute the depth of a document. More...

Json_dom_ptr	clone () const override
	Make a deep clone. More...

void	replace_dom_in_container (const Json_dom *oldv, Json_dom_ptr newv) override
	Replace oldv contained inside this container array or object) with newv. More...

void	clear ()
	Remove all elements in the object. More...

const_iterator	begin () const
	Returns a const_iterator that refers to the first element. More...

const_iterator	end () const
	Returns a const_iterator that refers past the last element. More...

bool	merge_patch (Json_object_ptr patch)
	Implementation of the MergePatch function specified in RFC 7396: More...

Public Member Functions inherited from Json_dom
virtual	~Json_dom ()=default

void *	operator new (size_t size, const std::nothrow_t &) noexcept
	Allocate space on the heap for a Json_dom object. More...

void	operator delete (void *ptr) noexcept
	Deallocate the space used by a Json_dom object. More...

void	operator delete (void *ptr, const std::nothrow_t &) noexcept
	Nothrow delete. More...

Json_container *	parent () const
	Get the parent dom to which this dom is attached. More...

virtual bool	is_scalar () const

virtual bool	is_number () const

Json_path	get_location () const
	Get the path location of this dom, measured from the outermost document it nests inside. More...

bool	seek (const Json_seekable_path &path, size_t legs, Json_dom_vector *hits, bool auto_wrap, bool only_need_one)
	Finds all of the json sub-documents which match the path expression. More...

Private Attributes
Json_object_map	m_map
	Map to hold the object elements. More...

Additional Inherited Members
Static Public Member Functions inherited from Json_dom
static Json_dom_ptr	parse (const char *text, size_t length, const JsonParseErrorHandler &error_handler, const JsonErrorHandler &depth_handler)
	Parse Json text to DOM (using rapidjson). More...

static Json_dom_ptr	parse (const json_binary::Value &v)
	Construct a DOM object based on a binary JSON value. More...

Detailed Description

Represents a JSON container value of type "object" (ECMA), type J_OBJECT here.

Member Typedef Documentation

◆ const_iterator

typedef Json_object_map::const_iterator Json_object::const_iterator

Constant iterator over the elements in the JSON object.

Each element is represented as a std::pair where first is a std::string that represents the key name, and second is a pointer to a Json_dom that represents the value.

Constructor & Destructor Documentation

◆ Json_object()

Json_object::Json_object ( )

Member Function Documentation

◆ add_alias() [1/2]

bool Json_object::add_alias	(	const std::string &	key,
		Json_dom *	value
	)

inline

Insert the value into the object.

If the key already exists in the object, the existing value is replaced ("last value wins").

Ownership of the value is effectively transferred to the object and the value will be deallocated by the object so only add values that can be deallocated safely (no stack variables please!)

New code should prefer add_alias(const std::string&, Json_dom_ptr) to this function, because that makes the transfer of ownership more explicit. This function might be removed in the future.

Parameters

[in]	key	the JSON key of to be added
[in]	value	a JSON value: the key's value

Return values

false	on success
true	on failure

◆ add_alias() [2/2]

bool Json_object::add_alias	(	const std::string &	key,
		Json_dom_ptr	value
	)

Insert the value into the object.

If the key already exists in the object, the existing value is replaced ("last value wins").

The ownership of the value is transferred to the object.

Parameters

[in]	key	the key of the value to be added
[in]	value	the value to add

Returns: false on success, true on failure

◆ add_clone()

bool Json_object::add_clone	(	const std::string &	key,
		const Json_dom *	value
	)

inline

Insert a clone of the value into the object.

If the key already exists in the object, the existing value is replaced ("last value wins").

Parameters

[in]	key	the JSON element key of to be added
[in]	value	a JSON value: the element key's value

Return values

false	on success
true	on failure

◆ begin()

const_iterator Json_object::begin ( ) const

inline

Returns a const_iterator that refers to the first element.

◆ cardinality()

size_t Json_object::cardinality ( ) const

Returns: The number of elements in the JSON object.

◆ clear()

void Json_object::clear ( )

inline

Remove all elements in the object.

◆ clone()

Json_dom_ptr Json_object::clone ( ) const

overridevirtual

Make a deep clone.

The ownership of the returned object is henceforth with the caller.

Returns: a cloned Json_dom object.

Implements Json_dom.

◆ consume()

bool Json_object::consume ( Json_object_ptr other )

Transfer all of the key/value pairs in the other object into this object.

The other object is deleted. If this object and the other object share a key, then the two values of the key are merged.

Parameters

[in] other a pointer to the object which will be consumed

Return values

false	on success
true	on failure

◆ depth()

uint32 Json_object::depth ( ) const

overridevirtual

Compute the depth of a document.

This is the value which would be returned by the JSON_DEPTH() system function.

for scalar values, empty array and empty object: 1
for non-empty array: 1+ max(depth of array elements)
for non-empty objects: 1+ max(depth of object values)

For example: "abc", [] and {} have depth 1. ["abc", [3]] and {"a": "abc", "b": [3]} have depth 3.

Returns: the depth of the document

Implements Json_dom.

◆ end()

const_iterator Json_object::end ( ) const

inline

Returns a const_iterator that refers past the last element.

◆ get() [1/2]

Json_dom * Json_object::get ( const MYSQL_LEX_CSTRING & key ) const

◆ get() [2/2]

Json_dom * Json_object::get ( const std::string & key ) const

Return the value at key.

The value is not cloned, so make one if you need it. Do not delete the returned value, please! If the key is not present, return a null pointer.

Parameters

[in] key the key of the element whose value we want

Returns: the value associated with the key, or NULL if the key is not found

◆ json_type()

enum_json_type Json_object::json_type ( ) const

inlineoverridevirtual

Returns: the type corresponding to the actual Json_dom subclass

Implements Json_dom.

◆ merge_patch()

bool Json_object::merge_patch ( Json_object_ptr patch )

Implementation of the MergePatch function specified in RFC 7396:

define MergePatch(Target, Patch):
  if Patch is an Object:
    if Target is not an Object:
      Target = {} # Ignore the contents and set it to an empty Object
    for each Key/Value pair in Patch:
      if Value is null:
        if Key exists in Target:
          remove the Key/Value pair from Target
      else:
        Target[Key] = MergePatch(Target[Key], Value)
    return Target
  else:
    return Patch

Parameters

patch the object that describes the patch

Return values

false	on success
true	on memory allocation error

◆ remove()

bool Json_object::remove ( const std::string & key )

Remove the child element addressed by key.

The removed child is deleted.

Parameters

key	the key of the element to remove

Return values

true	if an element was removed
false	if there was no element with that key

◆ replace_dom_in_container()

void Json_object::replace_dom_in_container	(	const Json_dom *	oldv,
		Json_dom_ptr	newv
	)

overridevirtual

Replace oldv contained inside this container array or object) with newv.

If this container does not contain oldv, calling the method is a no-op.

Parameters

[in]	oldv	the value to be replaced
[in]	newv	the new value to put in the container

Implements Json_container.

Member Data Documentation

◆ m_map

Json_object_map Json_object::m_map

private

Map to hold the object elements.

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

sql-common/json_dom.h
sql-common/json_dom.cc

Public Types

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ const_iterator

Constructor & Destructor Documentation

◆ Json_object()

Member Function Documentation

◆ add_alias() [1/2]

◆ add_alias() [2/2]

◆ add_clone()

◆ begin()

◆ cardinality()

◆ clear()

◆ clone()

◆ consume()

◆ depth()

◆ end()

◆ get() [1/2]

◆ get() [2/2]

◆ json_type()

◆ merge_patch()

◆ remove()

◆ replace_dom_in_container()

Member Data Documentation

◆ m_map