JSON Parser Callback

Detailed Description

JSON Parser Callback Interface.

Collaboration diagram for JSON Parser Callback:

Classes
struct	JParserValFact
	JParserValFact is the JVal JSON parser factory class. More...
struct	JParserIntf
	The JParserIntf interface class is the interface between the parser and an object that implements the JParserIntf interface. More...
struct	JDecoderStackNode
	Used internally in JDecoder for nested data structures. More...
struct	JDecoderV
	Used internally in JDecoder, where one instance represents one node in the pointer value tree. More...
struct	JDecoder
	JDecoder implements the parser callback API JParserIntf and builds a pointer value tree when JDecoder::get is called. More...

Macros
#define	JD_MNUM(o, m)   #m, &(o)->m
	JDecoder::get helper macro, used when setting a number pointer in an object. More...
#define	JD_MSTR(o, m)   #m, &(o)->m, sizeof((o)->m)
	JDecoder::get helper macro, used when setting a string pointer in an object. More...
#define	JD_ASTR(o, m)   &(o)->m, sizeof((o)->m)
	JDecoder::get helper macro, used when setting a string pointer in an array. More...

Typedefs
typedef JParserValFact	JParserValFact
	JParserValFact is the JVal JSON parser factory class. More...
typedef int(*	JParserIntf_Service) (struct JParserIntf *o, struct JParserVal *v, int recLevel)
	The parser callback function. More...
typedef struct JParserIntf	JParserIntf
	The JParserIntf interface class is the interface between the parser and an object that implements the JParserIntf interface.
typedef JDecoder	JDecoder
	JDecoder implements the parser callback API JParserIntf and builds a pointer value tree when JDecoder::get is called. More...

Enumerations
enum	JDecoderS {   JDecoderS_FormatErr = -100 , JDecoderS_NameNotFound , JDecoderS_Overflow , JDecoderS_StringOverflow ,   JDecoderS_Unbalanced , JDecoderS_Underflow , JDecoderS_Unknown , JDecoderS_BufNotAligned ,   JDecoderS_ChainedErr , JDecoderS_OK = 0 }
	JDecoder Status. More...

Functions
	JParserValFact::JParserValFact (AllocatorIntf *vAlloc, AllocatorIntf *dAlloc)
	create a JParserValFact JVal factory instance. More...
JVal *	JParserValFact::getFirstVal ()
	Returns the root of the JVal syntax tree.
JVal *	JParserValFact::manageFirstVal ()
	Similar to getFirstVal, but you must manage the JVal tree as the value is detached from the JParserValFact.
void	JParserValFact::termFirstVal ()
	Terminate the syntax tree such that the JParserValFact instance can be reused when the JParser instance parses the next JSON object in a stream.
	JParserValFact::~JParserValFact ()
	The destructor terminates all nodes not managed.
int	JParserIntf::serviceCB (JParserVal *v, int recLevel)
	Calling the JParserIntf service function is typically performed in a design using a chained parser callback interface. More...
int	JDecoder::vget (const char *fmt, va_list *argList)
	See JDecoder::get for details.
int	JDecoder::get (const char *fmt,...)
	Build a pointer value tree that is used by the integrated parser callback function when the parser feeds elements to the JDecoder instance. More...
	JDecoder::JDecoder (U8 *buf, int bufSize, int extraStackLen=0)
	Create/initialize a JDecoder instance. More...

Macro Definition Documentation

JD_ASTR

#define JD_ASTR	(		o,
			m
	)		&(o)->m, sizeof((o)->m)

JDecoder::get helper macro, used when setting a string pointer in an array.

encoder.set("[s]", JD_ASTR(structval, membername));

JD_MNUM

#define JD_MNUM	(		o,
			m
	)		#m, &(o)->m

JDecoder::get helper macro, used when setting a number pointer in an object.

encoder.set("{d}", JD_MNUM(structval, membername));

JD_MSTR

#define JD_MSTR	(		o,
			m
	)		#m, &(o)->m, sizeof((o)->m)

JDecoder::get helper macro, used when setting a string pointer in an object.

encoder.set("{s}", JD_MSTR(structval, membername));

Typedef Documentation

JDecoder

typedef JDecoder JDecoder

JDecoder implements the parser callback API JParserIntf and builds a pointer value tree when JDecoder::get is called.

The pointer value tree is used by the parser callback when the parser feeds the callback with parsed data.

See the JSON and UBJSON tutorial for more information on using JDecoder.

JParserIntf_Service

typedef int(* JParserIntf_Service) (struct JParserIntf *o, struct JParserVal *v, int recLevel)

The parser callback function.

Parameters

o	the interface object
v	the parsed value
recLevel	goes from 0 to N and represents object nesting level

JParserValFact

typedef JParserValFact JParserValFact

JParserValFact is the JVal JSON parser factory class.

An instance of this class is connected to an instance of the JParser. The JParser communicates with the JVal factory when parsing JSON, and the JVal factory creates JVal objects.

Method getFirstVal returns the first value in the syntax tree.

The class automatically manages the nodes allocated. The allocated nodes are automatically de-allocated when the destructor runs. You can manage the values by calling JParserValFact::manageFirstVal or by calling JVal::manageJ on any of the children.

See also

JValFact

JDecode

Enumeration Type Documentation

JDecoderS

enum JDecoderS

JDecoder Status.

Enumerator
JDecoderS_FormatErr	Parsed data does not match the value tree that was created when method JDecoder::get was called.
JDecoderS_NameNotFound	Parsed data includes a member whose name is not in value tree.
JDecoderS_Overflow	Received more array or object member values from parsed data than found in value tree.
JDecoderS_StringOverflow	Parsed string longer than buffer provided.
JDecoderS_Unbalanced	Incorrect use of '{', '}', '[', or '[' in JDecoder::get.
JDecoderS_Underflow	Received less array or object member values from parsed data than found in value tree.
JDecoderS_Unknown	Unkown error.
JDecoderS_BufNotAligned	Memory buffer(s) provided in JDecoder constructor must be word aligned.
JDecoderS_ChainedErr	A chained parser callback, provided via the 'X' format flag in JDecoder::get, reported an error.
JDecoderS_OK	OK, no errors.

Function Documentation

get()

int JDecoder::get	(	const char *	fmt,
			...
	)

Build a pointer value tree that is used by the integrated parser callback function when the parser feeds elements to the JDecoder instance.

Parameters

fmt	format flags: JSON type Format flag C type Number d S32* Number l S64* Number f double* boolean b BaBool* or U8* string s char** Start object { n/a End object } n/a Start array [ n/a End array ] n/a N/A X JParserIntf*

See the JSON and UBJSON tutorial for more information on using this method.

See also

JD_MNUM

JD_MSTR

JD_ASTR

JEncoder::set

JDecoder()

JDecoder::JDecoder	(	U8 *	buf,
		int	bufSize,
		int	extraStackLen = 0
	)

Create/initialize a JDecoder instance.

Parameters

buf	is a pointer to a buffer used internally for memory storage when building the pointer value tree. The minimum size must be sizeof(JDecoderV) * N, where N is the number of format flags minus the end of array/object flags (] or }).
bufSize	the size of 'buf'
extraStackLen	is a non documented value and must be set to 0.

JParserValFact()

JParserValFact::JParserValFact	(	AllocatorIntf *	vAlloc,
		AllocatorIntf *	dAlloc
	)

create a JParserValFact JVal factory instance.

Parameters

vAlloc	is used when allocating nodes.
dAlloc	is used when allocating strings. The two allocators can be the same.

serviceCB()

int JParserIntf::serviceCB	(	JParserVal *	v,
		int	recLevel
	)

Calling the JParserIntf service function is typically performed in a design using a chained parser callback interface.

Parameters

v	the parsed value provided by JParser
recLevel	must be adjusted by the chained callback