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Value Class Reference

Collaboration diagram for Value:

[legend]

List of all members.

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Detailed Description

Represents a JSON value.

This class is a discriminated union wrapper that can represents 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 obtanis 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.

Public Types
typedef std::vector < std::string >	Members
typedef ValueIterator	iterator
typedef ValueConstIterator	const_iterator
typedef JB_Json::UInt	UInt
typedef JB_Json::Int	Int
typedef JB_Json::UInt64	UInt64
typedef JB_Json::Int64	Int64
typedef JB_Json::LargestInt	LargestInt
typedef JB_Json::LargestUInt	LargestUInt
typedef JB_Json::ArrayIndex	ArrayIndex
typedef std::map < CZString, Value >	ObjectValues
Public Member Functions
	Value (ValueType type=nullValue)
	Value (Int value)
	Value (UInt value)
	Value (Int64 value)
	Value (UInt64 value)
	Value (double value)
	Value (const char *value)
	Value (const char *beginValue, const char *endValue)
	Value (const StaticString &value)
	Value (const std::string &value)
	Value (bool value)
	Value (const Value &other)
	Deep copy.
	~Value ()
Value &	operator= (const Value &other)
void	swap (Value &other)
	Swap everything.
void	swapPayload (Value &other)
	Swap values but leave comments and source offsets in place.
ValueType	type () const
bool	operator< (const Value &other) const
	Compare payload only, not comments etc.
bool	operator<= (const Value &other) const
bool	operator>= (const Value &other) const
bool	operator> (const Value &other) const
bool	operator== (const Value &other) const
bool	operator!= (const Value &other) const
int	compare (const Value &other) const
const char *	asCString () const
std::string	asString () const
Int	asInt () const
UInt	asUInt () const
Int64	asInt64 () const
UInt64	asUInt64 () const
LargestInt	asLargestInt () const
LargestUInt	asLargestUInt () const
float	asFloat () const
double	asDouble () const
bool	asBool () const
bool	isNull () const
bool	isBool () const
bool	isInt () const
bool	isInt64 () const
bool	isUInt () const
bool	isUInt64 () const
bool	isIntegral () const
bool	isDouble () const
bool	isNumeric () const
bool	isString () const
bool	isArray () const
bool	isObject () const
bool	isConvertibleTo (ValueType other) const
ArrayIndex	size () const
	Number of values in array or object.
bool	empty () const
bool	operator! () const
	Return isNull().
void	clear ()
	Remove all object members and array elements.
void	resize (ArrayIndex size)
	Resize the array to size elements. New elements are initialized to null. May only be called on nullValue or arrayValue.
Value &	operator[] (ArrayIndex 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.).
Value &	operator[] (int 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.).
const Value &	operator[] (ArrayIndex 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.).
const Value &	operator[] (int 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 (ArrayIndex index, const Value &defaultValue) const
	If the array contains at least index+1 elements, returns the element value, otherwise returns defaultValue.
bool	isValidIndex (ArrayIndex index) const
	Return true if index < size().
Value &	append (const Value &value)
Value &	operator[] (const char *key)
	Access an object value by name, create a null member if it does not exist.
const Value &	operator[] (const char *key) const
	Access an object value by name, returns null if there is no member with that name.
Value &	operator[] (const std::string &key)
	Access an object value by name, create a null member if it does not exist.
const Value &	operator[] (const std::string &key) const
	Access an object value by name, returns null if there is no member with that name.
Value &	operator[] (const StaticString &key)
Value	get (const char *key, const Value &defaultValue) const
	Return the member named key if it exist, defaultValue otherwise.
Value	get (const std::string &key, const Value &defaultValue) const
	Return the member named key if it exist, defaultValue otherwise.
Value	removeMember (const char *key)
Value	removeMember (const std::string &key)
	Same as removeMember(const char*).
bool	removeMember (const char *key, Value *removed)
bool	removeIndex (ArrayIndex i, Value *removed)
bool	isMember (const char *key) const
	Return true if the object has a member named key.
bool	isMember (const std::string &key) const
	Return true if the object has a member named key.
Members	getMemberNames () const
void	setComment (const char *comment, CommentPlacement placement)
void	setComment (const char *comment, size_t len, CommentPlacement placement)
	Comments must be //... or /* ... */.
void	setComment (const std::string &comment, CommentPlacement placement)
	Comments must be //... or /* ... */.
bool	hasComment (CommentPlacement placement) const
std::string	getComment (CommentPlacement placement) const
	Include delimiters and embedded newlines.
std::string	toStyledString () const
const_iterator	begin () const
const_iterator	end () const
iterator	begin ()
iterator	end ()
Static Public Attributes
static const Value &	nullRef = reinterpret_cast<const Value&>(kNullRef)
static const Value	null
static const LargestInt	minLargestInt = LargestInt(~(LargestUInt(-1) / 2))
	Minimum signed integer value that can be stored in a JB_Json::Value.
static const LargestInt	maxLargestInt = LargestInt(LargestUInt(-1) / 2)
	Maximum signed integer value that can be stored in a JB_Json::Value.
static const LargestUInt	maxLargestUInt = LargestUInt(-1)
	Maximum unsigned integer value that can be stored in a JB_Json::Value.
static const Int	minInt = Int(~(UInt(-1) / 2))
	Minimum signed int value that can be stored in a JB_Json::Value.
static const Int	maxInt = Int(UInt(-1) / 2)
	Maximum signed int value that can be stored in a JB_Json::Value.
static const UInt	maxUInt = UInt(-1)
	Maximum unsigned int value that can be stored in a JB_Json::Value.
static const Int64	minInt64 = Int64(~(UInt64(-1) / 2))
	Minimum signed 64 bits int value that can be stored in a JB_Json::Value.
static const Int64	maxInt64 = Int64(UInt64(-1) / 2)
	Maximum signed 64 bits int value that can be stored in a JB_Json::Value.
static const UInt64	maxUInt64 = UInt64(-1)
	Maximum unsigned 64 bits int value that can be stored in a JB_Json::Value.
Friends
class	ValueIteratorBase
Classes
struct	CommentInfo
class	CZString
union	ValueHolder

---

Member Typedef Documentation

typedef std::vector<std::string> Members

typedef ValueIterator iterator

typedef ValueConstIterator const_iterator

typedef JB_Json::UInt UInt

typedef JB_Json::Int Int

typedef JB_Json::UInt64 UInt64

typedef JB_Json::Int64 Int64

typedef JB_Json::LargestInt LargestInt

typedef JB_Json::LargestUInt LargestUInt

typedef JB_Json::ArrayIndex ArrayIndex

typedef std::map<CZString, Value> ObjectValues

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Constructor & Destructor Documentation

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:

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

Value

(

Int

value

)

Value

(

UInt

value

)

Value

(

Int64

value

)

Value

(

UInt64

value

)

Value

(

double

value

)

Value

(

const char *

value

)

Value	(	const char *	beginValue,
		const char *	endValue
	)

Value

(

const StaticString &

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:

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

Value

(

const std::string &

value

)

Value

(

bool

value

)

Value

(

const Value &

other

)

Deep copy.

~Value

(

)

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Member Function Documentation

Value & operator=

(

const Value &

other

)

void swap

(

Value &

other

)

Swap everything.

void swapPayload

(

Value &

other

)

Swap values but leave comments and source offsets in place.

ValueType type

(

)

const

bool operator<

(

const Value &

other

)

const

Compare payload only, not comments etc.

bool operator<=

(

const Value &

other

)

const

bool operator>=

(

const Value &

other

)

const

bool operator>

(

const Value &

other

)

const

bool operator==

(

const Value &

other

)

const

bool operator!=

(

const Value &

other

)

const

int compare

(

const Value &

other

)

const

const char * asCString

(

)

const

std::string asString

(

)

const

Value::Int asInt

(

)

const

Value::UInt asUInt

(

)

const

Value::Int64 asInt64

(

)

const

Value::UInt64 asUInt64

(

)

const

LargestInt asLargestInt

(

)

const

LargestUInt asLargestUInt

(

)

const

float asFloat

(

)

const

double asDouble

(

)

const

bool asBool

(

)

const

bool isNull

(

)

const

bool isBool

(

)

const

bool isInt

(

)

const

bool isInt64

(

)

const

bool isUInt

(

)

const

bool isUInt64

(

)

const

bool isIntegral

(

)

const

bool isDouble

(

)

const

bool isNumeric

(

)

const

bool isString

(

)

const

bool isArray

(

)

const

bool isObject

(

)

const

bool isConvertibleTo

(

ValueType

other

)

const

ArrayIndex size

(

)

const

Number of values in array or object.

bool empty

(

)

const

Return true if empty array, empty object, or null; otherwise, false.

bool operator!

(

)

const

Return isNull().

void clear

(

)

Remove all object members and array elements.

Precondition:

type() is arrayValue, objectValue, or nullValue

Postcondition:

type() is unchanged

void resize

(

ArrayIndex

size

)

Resize the array to size elements. New elements are initialized to null. May only be called on nullValue or arrayValue.

Precondition:

type() is arrayValue or nullValue

Postcondition:

type() is arrayValue

Value & operator[]

(

ArrayIndex

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.).

Value & operator[]

(

int

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.).

const Value & operator[]

(

ArrayIndex

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.).

const Value & operator[]

(

int

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	(	ArrayIndex	index,
		const Value &	defaultValue
	)			const

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

bool isValidIndex

(

ArrayIndex

index

)

const

Return true if index < size().

Value & append

(

const Value &

value

)

Append value to array at the end. Equivalent to jsonvalue[jsonvalue.size()] = value;

Value & operator[]

(

const char *

key

)

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

const Value & operator[]

(

const char *

key

)

const

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

Value & operator[]

(

const std::string &

key

)

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

const Value & operator[]

(

const std::string &

key

)

const

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

Value & operator[]

(

const StaticString &

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:

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

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

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

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

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

Value removeMember

(

const char *

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

Deprecated:

Value removeMember

(

const std::string &

key

)

Same as removeMember(const char*).

Deprecated:

bool removeMember	(	const char *	key,
		Value *	removed
	)

Remove the named map member.

Update 'removed' iff removed.

Returns:

true iff removed (no exceptions)

bool removeIndex	(	ArrayIndex	i,
		Value *	removed
	)

Remove the indexed array element.

O(n) expensive operations. Update 'removed' iff removed.

Returns:

true iff removed (no exceptions)

bool isMember

(

const char *

key

)

const

Return true if the object has a member named key.

bool isMember

(

const std::string &

key

)

const

Return true if the object has a member named key.

Value::Members 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

void setComment	(	const char *	comment,
		CommentPlacement	placement
	)

Deprecated:

Always pass len.

void setComment	(	const char *	comment,
		size_t	len,
		CommentPlacement	placement
	)

Comments must be //... or /* ... */.

void setComment	(	const std::string &	comment,
		CommentPlacement	placement
	)

Comments must be //... or /* ... */.

bool hasComment

(

CommentPlacement

placement

)

const

std::string getComment

(

CommentPlacement

placement

)

const

Include delimiters and embedded newlines.

std::string toStyledString

(

)

const

Value::const_iterator begin

(

)

const

Value::const_iterator end

(

)

const

Value::iterator begin

(

)

Value::iterator end

(

)

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Friends And Related Function Documentation

friend class ValueIteratorBase [friend]

---

Member Data Documentation

const Value & nullRef = reinterpret_cast<const Value&>(kNullRef) [static]

const Value null [static]

Deprecated:

This exists for binary compatibility only. Use nullRef.

const LargestInt minLargestInt = LargestInt(~(LargestUInt(-1) / 2)) [static]

Minimum signed integer value that can be stored in a JB_Json::Value.

const LargestInt maxLargestInt = LargestInt(LargestUInt(-1) / 2) [static]

Maximum signed integer value that can be stored in a JB_Json::Value.

const LargestUInt maxLargestUInt = LargestUInt(-1) [static]

Maximum unsigned integer value that can be stored in a JB_Json::Value.

const Int minInt = Int(~(UInt(-1) / 2)) [static]

Minimum signed int value that can be stored in a JB_Json::Value.

const Int maxInt = Int(UInt(-1) / 2) [static]

Maximum signed int value that can be stored in a JB_Json::Value.

const UInt maxUInt = UInt(-1) [static]

Maximum unsigned int value that can be stored in a JB_Json::Value.

const Int64 minInt64 = Int64(~(UInt64(-1) / 2)) [static]

Minimum signed 64 bits int value that can be stored in a JB_Json::Value.

const Int64 maxInt64 = Int64(UInt64(-1) / 2) [static]

Maximum signed 64 bits int value that can be stored in a JB_Json::Value.

const UInt64 maxUInt64 = UInt64(-1) [static]

Maximum unsigned 64 bits int value that can be stored in a JB_Json::Value.

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