Oxygine  1
2g game engine
Classes | Public Types | Public Member Functions | Static Public Attributes | Friends | List of all members
Json::Value Class Reference

Represents a JSON value. More...

#include <json.h>

Public Types

typedef std::vector< std::string > Members
 
typedef ValueIterator iterator
 
typedef ValueConstIterator const_iterator
 
typedef Json::UInt UInt
 
typedef Json::Int Int
 
typedef Json::UInt64 UInt64
 
typedef Json::Int64 Int64
 
typedef Json::LargestInt LargestInt
 
typedef Json::LargestUInt LargestUInt
 
typedef Json::ArrayIndex ArrayIndex
 
typedef std::map< CZString, ValueObjectValues
 

Public Member Functions

 Value (ValueType type=nullValue)
 Create a default Value of the given type. More...
 
 Value (Int value)
 
 Value (UInt value)
 
 Value (Int64 value)
 
 Value (UInt64 value)
 
 Value (double value)
 
 Value (const char *value)
 Copy til first 0. (NULL causes to seg-fault.)
 
 Value (const char *begin, const char *end)
 Copy all, incl zeroes.
 
 Value (const StaticString &value)
 Constructs a value from a static string. More...
 
 Value (const std::string &value)
 Copy data() til size(). Embedded zeroes too.
 
 Value (bool value)
 
 Value (const Value &other)
 Deep copy.
 
Valueoperator= (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
 Embedded zeroes could cause you trouble!
 
std::string asString () const
 Embedded zeroes are possible.
 
bool getString (char const **begin, char const **end) 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
 Return true if empty array, empty object, or null; otherwise, false.
 
bool operator! () const
 Return isNull()
 
void clear ()
 
void resize (ArrayIndex size)
 
Valueoperator[] (ArrayIndex index)
 
Valueoperator[] (int index)
 
const Valueoperator[] (ArrayIndex index) const
 
const Valueoperator[] (int index) const
 
Value get (ArrayIndex index, const Value &defaultValue) const
 
bool isValidIndex (ArrayIndex index) const
 Return true if index < size().
 
Valueappend (const Value &value)
 Append value to array at the end. More...
 
Valueoperator[] (const char *key)
 
const Valueoperator[] (const char *key) const
 
Valueoperator[] (const std::string &key)
 
const Valueoperator[] (const std::string &key) const
 
Valueoperator[] (const StaticString &key)
 Access an object value by name, create a null member if it does not exist. More...
 
Value get (const char *key, const Value &defaultValue) const
 
Value get (const char *begin, const char *end, const Value &defaultValue) const
 
Value get (const std::string &key, const Value &defaultValue) const
 
Value const * find (char const *begin, char const *end) const
 
Value const * demand (char const *begin, char const *end)
 
Value removeMember (const char *key)
 Remove and return the named member. More...
 
Value removeMember (const std::string &key)
 
bool removeMember (const char *key, Value *removed)
 
bool removeMember (std::string const &key, Value *removed)
 Remove the named map member. More...
 
bool removeMember (const char *begin, const char *end, Value *removed)
 Same as removeMember(std::string const& key, Value* removed)
 
bool removeIndex (ArrayIndex i, Value *removed)
 Remove the indexed array element. More...
 
bool isMember (const char *key) const
 
bool isMember (const std::string &key) const
 
bool isMember (const char *begin, const char *end) const
 Same as isMember(std::string const& key)const.
 
Members getMemberNames () const
 Return a list of the member names. More...
 
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 ValuenullRef
 
static const Value null
 
static const LargestInt minLargestInt
 Minimum signed integer value that can be stored in a Json::Value.
 
static const LargestInt maxLargestInt
 Maximum signed integer value that can be stored in a Json::Value.
 
static const LargestUInt maxLargestUInt
 Maximum unsigned integer value that can be stored in a Json::Value.
 
static const Int minInt
 Minimum signed int value that can be stored in a Json::Value.
 
static const Int maxInt
 Maximum signed int value that can be stored in a Json::Value.
 
static const UInt maxUInt
 Maximum unsigned int value that can be stored in a Json::Value.
 
static const Int64 minInt64
 Minimum signed 64 bits int value that can be stored in a Json::Value.
 
static const Int64 maxInt64
 Maximum signed 64 bits int value that can be stored in a Json::Value.
 
static const UInt64 maxUInt64
 Maximum unsigned 64 bits int value that can be stored in a Json::Value.
 

Friends

class ValueIteratorBase
 

Detailed Description

Represents a JSON value.

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

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 resized and initialized with nullValue. resize() can be used to enlarge or truncate an arrayValue.

The get() methods can be used to obtain 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.

Note
Value string-length fit in size_t, but keys must be < 2^30. (The reason is an implementation detail.) A #CharReader will raise an exception if a bound is exceeded to avoid security holes in your app, but the Value API does not check bounds. That is the responsibility of the caller.

Constructor & Destructor Documentation

§ Value() [1/2]

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); // {}

§ Value() [2/2]

Json::Value::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.

Note
This works only for null-terminated strings. (We cannot change the size of this class, so we have nowhere to store the length, which might be computed later for various operations.)

Example of usage:

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

Member Function Documentation

§ append()

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

Append value to array at the end.

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

§ clear()

void Json::Value::clear ( )

Remove all object members and array elements.

Precondition
type() is arrayValue, objectValue, or nullValue
Postcondition
type() is unchanged

§ demand()

Value const* Json::Value::demand ( char const *  begin,
char const *  end 
)

Most general and efficient version of object-mutators.

Note
As stated elsewhere, behavior is undefined if (end-begin) >= 2^30
Returns
non-zero, but JSON_ASSERT if this is neither object nor nullValue.

§ find()

Value const* Json::Value::find ( char const *  begin,
char const *  end 
) const

Most general and efficient version of isMember()const, get()const, and operator[]const

Note
As stated elsewhere, behavior is undefined if (end-begin) >= 2^30

§ get() [1/4]

Value Json::Value::get ( ArrayIndex  index,
const Value defaultValue 
) const

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

§ get() [2/4]

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

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

Note
deep copy

§ get() [3/4]

Value Json::Value::get ( const char *  begin,
const char *  end,
const Value defaultValue 
) const

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

Note
deep copy
key may contain embedded nulls.

§ get() [4/4]

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

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

Note
deep copy
Parameters
keymay contain embedded nulls.

§ getMemberNames()

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

§ getString()

bool Json::Value::getString ( char const **  begin,
char const **  end 
) const

Get raw char* of string-value.

Returns
false if !string. (Seg-fault if str or end are NULL.)

§ isMember() [1/2]

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

Return true if the object has a member named key.

Note
'key' must be null-terminated.

§ isMember() [2/2]

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

Return true if the object has a member named key.

Parameters
keymay contain embedded nulls.

§ operator=()

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

Deep copy, then swap(other).

Note
Over-write existing comments. To preserve comments, use swapPayload().

§ operator[]() [1/9]

Value& Json::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.)

§ operator[]() [2/9]

Value& Json::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.)

§ operator[]() [3/9]

const Value& Json::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.)

§ operator[]() [4/9]

const Value& Json::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.)

§ operator[]() [5/9]

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

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

Note
Because of our implementation, keys are limited to 2^30 -1 chars. Exceeding that will cause an exception.

§ operator[]() [6/9]

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

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

§ operator[]() [7/9]

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

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

Parameters
keymay contain embedded nulls.

§ operator[]() [8/9]

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

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

Parameters
keymay contain embedded nulls.

§ operator[]() [9/9]

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

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

If the object has 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;

§ removeIndex()

bool Json::Value::removeIndex ( ArrayIndex  i,
Value removed 
)

Remove the indexed array element.

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

Returns
true iff removed (no exceptions)

§ removeMember() [1/4]

Value Json::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:

§ removeMember() [2/4]

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

Same as removeMember(const char*)

Parameters
keymay contain embedded nulls.
Deprecated:

§ removeMember() [3/4]

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

§ removeMember() [4/4]

bool Json::Value::removeMember ( std::string const &  key,
Value removed 
)

Remove the named map member.

Update 'removed' iff removed.

Parameters
keymay contain embedded nulls.
Returns
true iff removed (no exceptions)

§ resize()

void Json::Value::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

§ setComment()

void Json::Value::setComment ( const char *  comment,
CommentPlacement  placement 
)
Deprecated:
Always pass len.

Member Data Documentation

§ null

const Value Json::Value::null
static
Deprecated:
This exists for binary compatibility only. Use nullRef.

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