JAULA::Parser::Value_Parser Class Reference

JSON Value Parser. More...

Public Member Functions
	Value_Parser (void)
	Constructor.
	~Value_Parser (void)
	Destructor.

Static Public Member Functions
static Value *	parseValue (Lexan &lexan, unsigned int token) throw (Exception)
	reads a single JSON value

Private Types
enum	parser_states {   START , array_addItem , array_nextItem , error ,   false_value , null_value , number_int_value , number_value ,   property_begin , property_name , property_value , property_next ,   string_value , true_value , END }
	Enumeration for the parser state machine. More...

Static Private Member Functions
static void	EOFError (Lexan &lexan, Syntax_Error const &ex) throw (Exception)
	Analyzes the reason for an EOF condition.

Detailed Description

JSON Value Parser.

Parses a value from the input stream.

Author

Kombo Morongo moron.nosp@m.go66.nosp@m.6@gma.nosp@m.il.c.nosp@m.om

Member Enumeration Documentation

parser_states

enum JAULA::Parser::Value_Parser::parser_states

private

Enumeration for the parser state machine.

Description

This type defines a constant for each state that the parser may assume during the process.

Enumerator
START	initial state
array_addItem	a new item for an array has been read
array_nextItem	an inter-item delimiter for an array has been read
error	error condition detected (pseudostate that launches an exception terminating the process)
false_value	a boolean false value constant has been read (pseudostate)
null_value	a null value constant has been read (pseudostate)
number_int_value	a numeric (integer) value has been read (pseudostate)
number_value	a numeric (float) value has been read (pseudostate)
property_begin	an object initial delimiter has been read
property_name	an object property name has been read
property_value	an object property delimiter has been read
property_next	an inter-property delimiter for an object has been read
string_value	a string value has been read (pseudostate)
true_value	a boolean true value constant has been read (pseudostate)
END	final state (pseudostate)

Constructor & Destructor Documentation

Value_Parser()

JAULA::Parser::Value_Parser::Value_Parser

(

void

)

Constructor.

~Value_Parser()

JAULA::Parser::Value_Parser::~Value_Parser

(

void

)

Destructor.

Member Function Documentation

EOFError()

void JAULA::Parser::Value_Parser::EOFError ( Lexan & lexan, Syntax_Error const & ex ) throw ( Exception )

staticprivate

Analyzes the reason for an EOF condition.

Parameters

lexan	Reference to the lexical analysis instance that reads from the input.
ex	Syntax error to be thrown detailing why an EOF at this point is an error.

Exceptions

Exception

As a result of the execution of this method an exception is thrown with the data conatined in the input parameter or with a JAULA::LEXAN_ERROR type if the EOF is due to an error in the lexical analysis phase.

Description

This method is to be launched whenever an unexpected end of file is encountered. Its implementation includes analyzing if the EOF condition is real or a side effect from a lexical analysis error and chooses to send the Lexan::LexerError Exception or the one received in the input parameter based on this.

References JAULA::Exception::addOrigin().

Referenced by parseValue().

parseValue()

Value * JAULA::Parser::Value_Parser::parseValue ( Lexan & lexan, unsigned int token ) throw ( Exception )

static

reads a single JSON value

Parameters

lexan	Reference to the lexical analysis instance that reads from the input.
token	Token read from the upper level. If this token does not belong to an starting value token, an error condition will arise.

Returns

a pointer to memory taken from the heap containing the value read. If this value belongs to a complex type, all the items that it contains have been recursively parsed.

Exceptions

Exception

An exception will be thrown as soon as a lexical or syntax error is found analyzing the stream. The result of printing the exception retrurned through a stream is a human readable text explaining the error found and an approximation of the error line where it occurred.

Description

This method fully reads a whole value from the input or until a syntax or lexical error is found. Upon execution input stream is positioned so that a new token or EOF can be read from the input.

References JAULA::Exception::addOrigin(), array_addItem, array_nextItem, END, EOFError(), JAULA::Value_String::getData(), parseValue(), property_begin, property_name, property_next, property_value, and START.

Referenced by JAULA::Parser::parseStream(), and parseValue().

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

• jaula_parse.h
• jaula_parse.cc