Represents a JSON value. More...

#include <json_value.h>

Collaboration diagram for Json::Value:

[legend]

Classes
class	CZString

union	ValueHolder

Public Types
using	Members = std::vector< std::string >

using	iterator = ValueIterator

using	const_iterator = ValueConstIterator

using	UInt = Json::UInt

using	Int = Json::Int

using	ArrayIndex = UInt

using	ObjectValues = std::map< CZString, Value >

Public Member Functions
	Value (ValueType type=nullValue)
	Create a default Value of the given type.

	Value (Int value)

	Value (UInt value)

	Value (double value)

	Value (char const *value)

	Value (xrpl::Number const &value)

	Value (StaticString const &value)
	Constructs a value from a static string.

	Value (std::string const &value)

	Value (bool value)

	Value (Value const &other)

	~Value ()

Value &	operator= (Value const &other)

Value &	operator= (Value &&other)

	Value (Value &&other) noexcept

void	swap (Value &other) noexcept
	Swap values.

ValueType	type () const

char const *	asCString () const

std::string	asString () const
	Returns the unquoted string value.

Int	asInt () const

UInt	asUInt () const

double	asDouble () const

bool	asBool () const

UInt	asAbsUInt () const
	Correct absolute value from int or unsigned int.

bool	isNull () const
	isNull() tests to see if this field is null.

bool	isBool () const

bool	isInt () const

bool	isUInt () const

bool	isIntegral () const

bool	isDouble () const

bool	isNumeric () const

bool	isString () const

bool	isArray () const

bool	isArrayOrNull () const

bool	isObject () const

bool	isObjectOrNull () const

bool	isConvertibleTo (ValueType other) const

UInt	size () const
	Number of values in array or object.

	operator bool () const
	Returns false if this is an empty array, empty object, empty string, or null.

void	clear ()
	Remove all object members and array elements.

Value &	operator[] (UInt index)
	Access an array element (zero based index ).

Value const &	operator[] (UInt index) const
	Access an array element (zero based index ) (You may need to say 'value[0u]' to get your compiler to distinguish this from the operator[] which takes a string.)

Value	get (UInt index, Value const &defaultValue) const
	If the array contains at least index+1 elements, returns the element value, otherwise returns defaultValue.

bool	isValidIndex (UInt index) const
	Return true if index < size().

Value &	append (Value const &value)
	Append value to array at the end.

Value &	append (Value &&value)

Value &	operator[] (char const *key)
	Access an object value by name, create a null member if it does not exist.

Value const &	operator[] (char const *key) const
	Access an object value by name, returns null if there is no member with that name.

Value &	operator[] (std::string const &key)
	Access an object value by name, create a null member if it does not exist.

Value const &	operator[] (std::string const &key) const
	Access an object value by name, returns null if there is no member with that name.

Value &	operator[] (StaticString const &key)
	Access an object value by name, create a null member if it does not exist.

Value const &	operator[] (StaticString const &key) const

Value	get (char const *key, Value const &defaultValue) const
	Return the member named key if it exist, defaultValue otherwise.

Value	get (std::string const &key, Value const &defaultValue) const
	Return the member named key if it exist, defaultValue otherwise.

Value	removeMember (char const *key)
	Remove and return the named member.

Value	removeMember (std::string const &key)
	Same as removeMember(const char*)

bool	isMember (char const *key) const
	Return true if the object has a member named key.

bool	isMember (std::string const &key) const
	Return true if the object has a member named key.

bool	isMember (StaticString const &key) const
	Return true if the object has a member named key.

Members	getMemberNames () const
	Return a list of the member names.

std::string	toStyledString () const

const_iterator	begin () const

const_iterator	end () const

iterator	begin ()

iterator	end ()

Static Public Attributes
static Value const	null

static constexpr Int	minInt = std::numeric_limits<Int>::min()

static constexpr Int	maxInt = std::numeric_limits<Int>::max()

static constexpr UInt	maxUInt = std::numeric_limits<UInt>::max()

Private Member Functions
Value &	resolveReference (char const *key, bool isStatic)

Private Attributes
union Json::Value::ValueHolder	value_

ValueType	type_: 8

int	allocated_: 1

Friends
class	ValueIteratorBase

bool	operator== (Value const &, Value const &)

bool	operator< (Value const &, Value const &)

Detailed Description

Represents a JSON value.

This class is a discriminated union wrapper that can represent a:

signed integer [range: Value::minInt - Value::maxInt]
unsigned integer (range: 0 - Value::maxUInt)
double
UTF-8 string
boolean
'null'
an ordered list of Value
collection of name/value pairs (javascript object)

The type of the held value is represented by a ValueType and can be obtained using type().

values of an objectValue or arrayValue can be accessed using operator[]() methods. Non const methods will automatically create the a nullValue element if it does not exist. The sequence of an arrayValue will be automatically resize and initialized with nullValue. resize() can be used to enlarge or truncate an arrayValue.

The get() methods can be used to obtain a default value in the case the required element does not exist.

It is possible to iterate over the list of a objectValue values using the getMemberNames() method.

Definition at line 129 of file json_value.h.

Member Typedef Documentation

◆ Members

using Json::Value::Members = std::vector<std::string>

Definition at line 134 of file json_value.h.

◆ iterator

using Json::Value::iterator = ValueIterator

Definition at line 135 of file json_value.h.

◆ const_iterator

using Json::Value::const_iterator = ValueConstIterator

Definition at line 136 of file json_value.h.

◆ UInt

using Json::Value::UInt = Json::UInt

Definition at line 137 of file json_value.h.

◆ Int

using Json::Value::Int = Json::Int

Definition at line 138 of file json_value.h.

◆ ArrayIndex

using Json::Value::ArrayIndex = UInt

Definition at line 139 of file json_value.h.

◆ ObjectValues

using Json::Value::ObjectValues = std::map<CZString, Value>

Definition at line 174 of file json_value.h.

Constructor & Destructor Documentation

◆ Value() [1/11]

Json::Value::Value ( ValueType type = nullValue )

Create a default Value of the given type.

This is a very useful constructor. To create an empty array, pass arrayValue. To create an empty object, pass objectValue. Another Value can then be set to this one by assignment. This is useful since clear() and resize() will not alter types.

   Examples:

Json::Value null_value; // null
Json::Value arr_value(Json::arrayValue); // []
Json::Value obj_value(Json::objectValue); // {}

Definition at line 158 of file json_value.cpp.

◆ Value() [2/11]

Json::Value::Value ( Int value )

Definition at line 194 of file json_value.cpp.

◆ Value() [3/11]

Json::Value::Value ( UInt value )

Definition at line 199 of file json_value.cpp.

◆ Value() [4/11]

Json::Value::Value ( double value )

Definition at line 204 of file json_value.cpp.

◆ Value() [5/11]

Json::Value::Value ( char const * value )

Definition at line 209 of file json_value.cpp.

◆ Value() [6/11]

Json::Value::Value ( xrpl::Number const & value )

Definition at line 214 of file json_value.cpp.

◆ Value() [7/11]

Json::Value::Value ( StaticString const & value )

Constructs a value from a static string.

Like other value string constructor but do not duplicate the string for internal storage. The given string must remain alive after the call to this constructor. Example of usage:

Json::Value aValue( StaticString("some text") );

Json::StaticString

Lightweight wrapper to tag static string.

Definition json_value.h:44

Definition at line 225 of file json_value.cpp.

◆ Value() [8/11]

Json::Value::Value ( std::string const & value )

Definition at line 220 of file json_value.cpp.

◆ Value() [9/11]

Json::Value::Value ( bool value )

Definition at line 230 of file json_value.cpp.

◆ Value() [10/11]

Json::Value::Value ( Value const & other )

Definition at line 235 of file json_value.cpp.

◆ ~Value()

Json::Value::~Value ( )

Definition at line 270 of file json_value.cpp.

◆ Value() [11/11]

Json::Value::Value ( Value && other )

noexcept

Definition at line 308 of file json_value.cpp.

Member Function Documentation

◆ operator=() [1/2]

Value & Json::Value::operator= ( Value const & other )

Definition at line 301 of file json_value.cpp.

◆ operator=() [2/2]

Value & Json::Value::operator= ( Value && other )

Definition at line 315 of file json_value.cpp.

◆ swap()

void Json::Value::swap ( Value & other )

noexcept

Swap values.

Definition at line 323 of file json_value.cpp.

◆ type()

ValueType Json::Value::type ( ) const

Definition at line 337 of file json_value.cpp.

◆ asCString()

char const * Json::Value::asCString ( ) const

Definition at line 450 of file json_value.cpp.

◆ asString()

std::string Json::Value::asString ( ) const

Returns the unquoted string value.

Definition at line 457 of file json_value.cpp.

◆ asInt()

Value::Int Json::Value::asInt ( ) const

Definition at line 493 of file json_value.cpp.

◆ asUInt()

Value::UInt Json::Value::asUInt ( ) const

Definition at line 590 of file json_value.cpp.

◆ asDouble()

double Json::Value::asDouble ( ) const

Definition at line 630 of file json_value.cpp.

◆ asBool()

bool Json::Value::asBool ( ) const

Definition at line 664 of file json_value.cpp.

◆ asAbsUInt()

UInt Json::Value::asAbsUInt ( ) const

Correct absolute value from int or unsigned int.

Definition at line 533 of file json_value.cpp.

◆ isNull()

bool Json::Value::isNull ( ) const

isNull() tests to see if this field is null.

Don't use this method to test for emptiness: use empty().

Definition at line 1019 of file json_value.cpp.

◆ isBool()

bool Json::Value::isBool ( ) const

Definition at line 1025 of file json_value.cpp.

◆ isInt()

bool Json::Value::isInt ( ) const

Definition at line 1031 of file json_value.cpp.

◆ isUInt()

bool Json::Value::isUInt ( ) const

Definition at line 1037 of file json_value.cpp.

◆ isIntegral()

bool Json::Value::isIntegral ( ) const

Definition at line 1043 of file json_value.cpp.

◆ isDouble()

bool Json::Value::isDouble ( ) const

Definition at line 1049 of file json_value.cpp.

◆ isNumeric()

bool Json::Value::isNumeric ( ) const

Definition at line 1055 of file json_value.cpp.

◆ isString()

bool Json::Value::isString ( ) const

Definition at line 1061 of file json_value.cpp.

◆ isArray()

bool Json::Value::isArray ( ) const

Definition at line 1067 of file json_value.cpp.

◆ isArrayOrNull()

bool Json::Value::isArrayOrNull ( ) const

Definition at line 1073 of file json_value.cpp.

◆ isObject()

bool Json::Value::isObject ( ) const

Definition at line 1079 of file json_value.cpp.

◆ isObjectOrNull()

bool Json::Value::isObjectOrNull ( ) const

Definition at line 1085 of file json_value.cpp.

◆ isConvertibleTo()

bool Json::Value::isConvertibleTo ( ValueType other ) const

Definition at line 698 of file json_value.cpp.

◆ size()

Value::UInt Json::Value::size ( ) const

Number of values in array or object.

Definition at line 746 of file json_value.cpp.

◆ operator bool()

Json::Value::operator bool ( ) const

explicit

Returns false if this is an empty array, empty object, empty string, or null.

Definition at line 780 of file json_value.cpp.

◆ clear()

void Json::Value::clear ( )

Remove all object members and array elements.

Precondition: type() is arrayValue, objectValue, or nullValue

Postcondition: type() is unchanged

Definition at line 795 of file json_value.cpp.

◆ operator[]() [1/8]

Value & Json::Value::operator[] ( UInt index )

Access an array element (zero based index ).

If the array contains less than index element, then null value are inserted in the array so that its size is index+1. (You may need to say 'value[0u]' to get your compiler to distinguish this from the operator[] which takes a string.)

Definition at line 812 of file json_value.cpp.

◆ operator[]() [2/8]

Value const & Json::Value::operator[] ( UInt index ) const

Access an array element (zero based index ) (You may need to say 'value[0u]' to get your compiler to distinguish this from the operator[] which takes a string.)

Definition at line 831 of file json_value.cpp.

◆ get() [1/3]

Value Json::Value::get	(	UInt	index,
		Value const &	defaultValue
	)		const

If the array contains at least index+1 elements, returns the element value, otherwise returns defaultValue.

Definition at line 874 of file json_value.cpp.

◆ isValidIndex()

bool Json::Value::isValidIndex ( UInt index ) const

Return true if index < size().

Definition at line 881 of file json_value.cpp.

◆ append() [1/2]

Value & Json::Value::append ( Value const & value )

Append value to array at the end.

Equivalent to jsonvalue[jsonvalue.size()] = value;

Definition at line 928 of file json_value.cpp.

◆ append() [2/2]

Value & Json::Value::append ( Value && value )

Definition at line 934 of file json_value.cpp.

◆ operator[]() [3/8]

Value & Json::Value::operator[] ( char const * key )

Access an object value by name, create a null member if it does not exist.

Definition at line 848 of file json_value.cpp.

◆ operator[]() [4/8]

Value const & Json::Value::operator[] ( char const * key ) const

Access an object value by name, returns null if there is no member with that name.

Definition at line 887 of file json_value.cpp.

◆ operator[]() [5/8]

Value & Json::Value::operator[] ( std::string const & key )

Access an object value by name, create a null member if it does not exist.

Definition at line 904 of file json_value.cpp.

◆ operator[]() [6/8]

Value const & Json::Value::operator[] ( std::string const & key ) const

Access an object value by name, returns null if there is no member with that name.

Definition at line 910 of file json_value.cpp.

◆ operator[]() [7/8]

Value & Json::Value::operator[] ( StaticString const & key )

Access an object value by name, create a null member if it does not exist.

If the object as no entry for that name, then the member name used to store the new entry is not duplicated. Example of use:

Json::Value object;
static const StaticString code("code");
object[code] = 1234;

Definition at line 916 of file json_value.cpp.

◆ operator[]() [8/8]

Value const & Json::Value::operator[] ( StaticString const & key ) const

Definition at line 922 of file json_value.cpp.

◆ get() [2/3]

Value Json::Value::get	(	char const *	key,
		Value const &	defaultValue
	)		const

Return the member named key if it exist, defaultValue otherwise.

Definition at line 940 of file json_value.cpp.

◆ get() [3/3]

Value Json::Value::get	(	std::string const &	key,
		Value const &	defaultValue
	)		const

Return the member named key if it exist, defaultValue otherwise.

Definition at line 947 of file json_value.cpp.

◆ removeMember() [1/2]

Value Json::Value::removeMember ( char const * key )

Remove and return the named member.

Do nothing if it did not exist.

Returns: the removed Value, or null.

Precondition: type() is objectValue or nullValue

Postcondition: type() is unchanged

Definition at line 953 of file json_value.cpp.

◆ removeMember() [2/2]

Value Json::Value::removeMember ( std::string const & key )

Same as removeMember(const char*)

Definition at line 972 of file json_value.cpp.

◆ isMember() [1/3]

bool Json::Value::isMember ( char const * key ) const

Return true if the object has a member named key.

Definition at line 978 of file json_value.cpp.

◆ isMember() [2/3]

bool Json::Value::isMember ( std::string const & key ) const

Return true if the object has a member named key.

Definition at line 988 of file json_value.cpp.

◆ isMember() [3/3]

bool Json::Value::isMember ( StaticString const & key ) const

Return true if the object has a member named key.

Definition at line 994 of file json_value.cpp.

◆ getMemberNames()

Value::Members Json::Value::getMemberNames ( ) const

Return a list of the member names.

If null, return an empty list.

Precondition: type() is objectValue or nullValue

Postcondition: if type() was nullValue, it remains nullValue

Definition at line 1000 of file json_value.cpp.

◆ toStyledString()

std::string Json::Value::toStyledString ( ) const

Definition at line 1091 of file json_value.cpp.

◆ begin() [1/2]

Value::const_iterator Json::Value::begin ( ) const

Definition at line 1098 of file json_value.cpp.

◆ end() [1/2]

Value::const_iterator Json::Value::end ( ) const

Definition at line 1116 of file json_value.cpp.

◆ begin() [2/2]

Value::iterator Json::Value::begin ( )

Definition at line 1134 of file json_value.cpp.

◆ end() [2/2]

Value::iterator Json::Value::end ( )

Definition at line 1151 of file json_value.cpp.

◆ resolveReference()

Value & Json::Value::resolveReference	(	char const *	key,
		bool	isStatic
	)

private

Definition at line 854 of file json_value.cpp.

Friends And Related Symbol Documentation

◆ ValueIteratorBase

friend class ValueIteratorBase

friend

Definition at line 131 of file json_value.h.

◆ operator==

bool operator==	(	Value const &	x,
		Value const &	y
	)

friend

Definition at line 404 of file json_value.cpp.

◆ operator<

bool operator<	(	Value const &	x,
		Value const &	y
	)

friend

Definition at line 353 of file json_value.cpp.

Member Data Documentation

◆ null

Value const Json::Value::null

static

Definition at line 141 of file json_value.h.

◆ minInt

constexpr Int Json::Value::minInt = std::numeric_limits<Int>::min()

staticconstexpr

Definition at line 142 of file json_value.h.

◆ maxInt

constexpr Int Json::Value::maxInt = std::numeric_limits<Int>::max()

staticconstexpr

Definition at line 143 of file json_value.h.

◆ maxUInt

constexpr UInt Json::Value::maxUInt = std::numeric_limits<UInt>::max()

staticconstexpr

Definition at line 144 of file json_value.h.

◆ value_

union Json::Value::ValueHolder Json::Value::value_

private

◆ type_

ValueType Json::Value::type_

private

Definition at line 423 of file json_value.h.

◆ allocated_

int Json::Value::allocated_

private

Definition at line 424 of file json_value.h.

Classes

Public Types

Public Member Functions

Static Public Attributes

Private Member Functions

Private Attributes

Friends

Detailed Description

Member Typedef Documentation

◆ Members

◆ iterator

◆ const_iterator

◆ UInt

◆ Int

◆ ArrayIndex

◆ ObjectValues

Constructor & Destructor Documentation

◆ Value() [1/11]

◆ Value() [2/11]

◆ Value() [3/11]

◆ Value() [4/11]

◆ Value() [5/11]

◆ Value() [6/11]

◆ Value() [7/11]

◆ Value() [8/11]

◆ Value() [9/11]

◆ Value() [10/11]

◆ ~Value()

◆ Value() [11/11]

Member Function Documentation

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ swap()

◆ type()

◆ asCString()

◆ asString()

◆ asInt()

◆ asUInt()

◆ asDouble()

◆ asBool()

◆ asAbsUInt()

◆ isNull()

◆ isBool()

◆ isInt()

◆ isUInt()

◆ isIntegral()

◆ isDouble()

◆ isNumeric()

◆ isString()

◆ isArray()

◆ isArrayOrNull()

◆ isObject()

◆ isObjectOrNull()

◆ isConvertibleTo()

◆ size()

◆ operator bool()

◆ clear()

◆ operator[]() [1/8]

◆ operator[]() [2/8]

◆ get() [1/3]

◆ isValidIndex()

◆ append() [1/2]

◆ append() [2/2]

◆ operator[]() [3/8]

◆ operator[]() [4/8]

◆ operator[]() [5/8]

◆ operator[]() [6/8]

◆ operator[]() [7/8]

◆ operator[]() [8/8]

◆ get() [2/3]

◆ get() [3/3]

◆ removeMember() [1/2]

◆ removeMember() [2/2]

◆ isMember() [1/3]

◆ isMember() [2/3]

◆ isMember() [3/3]

◆ getMemberNames()

◆ toStyledString()

◆ begin() [1/2]

◆ end() [1/2]