kfoundation::Token Class Reference

Represents a token in a stream. More...

#include <kfoundation/ObjectStreamReader.h>

Inheritance diagram for kfoundation::Token:

Public Member Functions
	Token (const CodeRange &cr)
	Constructor. More...
bool	is (const type_t &t) const
	Checks if the type of this token matches the given argument.
void	validateType (const type_t &t) const
	Checks of the type of this token matches the given argument, and if not, produces a ParseException explaning the problem.
Ref< ObjectToken >	asObject ()
	Validates if this token represents an object. More...
Ref< EndObjectToken >	asEndObject ()
	Validates if this token represents end of an object. More...
Ref< AttributeToken >	asAttribute ()
	Validates if this token represents an attribute. More...
Ref< CollectionToken >	asCollection ()
	Validates if this token represents begining of a collection. More...
Ref< EndCollectionToken >	asEndCollection ()
	Validates if this token represents end of a collection. More...
Public Member Functions inherited from kfoundation::ObjectStreamReader
virtual Ref< Token >	next ()=0 throw (ParseException)
	Returns the next token in the stream (not the token after this one).
Public Member Functions inherited from kfoundation::KFObject
bool	equals (RefConst< KFObject > other) const
	Checks if this object is the same as the one reffered by the given refrence.

Static Public Member Functions
static RefConst< UString >	toString (const type_t t)
	Returns a string corresponding the given parameter.

Public Attributes
const CodeRange	codeRange
	CodeRange marking begining and end of this token.

Detailed Description

Represents a token in a stream.

This is an abstract class. The actual object might be of any of the following types:

• ObjectToken
• AttributeToken
• EndObjectToken
• CollectionToken
• EndCollectionToken
• TextToken

Use getType() method to determine the type and cast accordingly. Most often this object is used in predictive parsing manner. For example:

 void deserialize(Ref<ObjectToken> headToken) {
     headToken->validateClass("MyClass");
     Ref<Token> token = headToken->next();
     token->validateType(Token::ATTRIBUTE);
     _name = token.AS(AttributeToken)->validateName("name")->getValue();
     token->next()->validateType(END_OBJECT);
 }

Conditional statements can be added if desired:

 void deserialize(Ref<ObjectToken> headToken) {
     headToken->validateClass("MyClass");
     Ref<Token> token = headToken->next();
     if(token.is(Token::ATTRIBUTE)) {
         Ref<AttributeToken> attrib = token.AS(Attribute);
         if(attrib->checkName("attrib1")) {
             _attrib1 = attrib->getValue();
         } else if(attrib->checkName("attrib2") {
             _attrib2 = attrib->getValue();
         } else {
             attrib->throwInvalidName();
         }
     } else {
         token->validateType(Token::OBJECT);
         ...
     }
     token->next()->validateType(END_OBJECT);
 }

validateXXX() methods cause an expection to be thrown if the given argument does not match the current token. The exception message will include a code location that helps the user to understand the problem.

See Also

ObjectDeserializer

Constructor & Destructor Documentation

kfoundation::Token::Token

(

const CodeRange &

cr)

Constructor.

Parameters

cr	The range marking the begining and the end of input containing this token.

Member Function Documentation

Ref< AttributeToken > kfoundation::Token::asAttribute

(

)

Validates if this token represents an attribute.

If so casts itself into AttributeToken, otherwise throws a ParseException.

Returns

Pointer to this object casted into AttributeToken.

Exceptions

ParseException

if the type of this token is not AttributeToken.

Ref< CollectionToken > kfoundation::Token::asCollection

(

)

Validates if this token represents begining of a collection.

If so casts itself into CollectionToken, otherwise throws a ParseException.

Returns

Pointer to this object casted into CollectionToken.

Exceptions

ParseException

if the type of this token is not CollectionToken.

Ref< EndCollectionToken > kfoundation::Token::asEndCollection

(

)

Validates if this token represents end of a collection.

If so casts itself into EndCollectionToken, otherwise throws a ParseException.

Returns

Pointer to this object casted into EndCollectionToken.

Exceptions

ParseException

if the type of this token is not EndCollectionToken.

Ref< EndObjectToken > kfoundation::Token::asEndObject

(

)

Validates if this token represents end of an object.

If so casts itself into EndObjectToken, otherwise throws a ParseException.

Returns

Pointer to this object casted into EndObjectToken.

Exceptions

ParseException

if the type of this token is not EndObjectToken.

Ref< ObjectToken > kfoundation::Token::asObject

(

)

Validates if this token represents an object.

If so casts itself into ObjectToken, otherwise throws a ParseException.

Returns

Pointer to this object casted into ObjectToken.

Exceptions

ParseException

if the type of this token is not ObjectToken.

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

• ObjectStreamReader.h
• ObjectStreamReader.cpp