Art::Paperback::Carousel::Object Class Reference

Represents a COS-file object. More...

#include <art/paperback/carousel/object.hxx>

Public Member Functions
	Object (Undefined const &)
	Constructor.
	Object (Array)
	Constructor.
	Object (Boolean)
	Constructor.
	Object (Dictionary)
	Constructor.
	Object (Integer)
	Constructor.
	Object (Name)
	Constructor.
	Object (Real)
	Constructor.
	Object (Text)
	Constructor.
	Object (Object const &)
	Constructor.
	Object (Object &&)
	Constructor.
void	attach (Object_model::Owner &)
	Attach object to owner.
bool	is_reference () const
	Check if the objcet is a reference.
Identity const &	identity () const
	Get object identity, if reference.
Object &	operator= (Object const &)
	Assignment.
Object &	operator= (Object &&)
	Assignment.
bool	operator== (Object const &) const
	Comparison.
bool	operator!= (Object const &) const
	Comparison.

Private Member Functions
	Object (shared_ptr< Object_model::Abstract >)
	Constructor.
Object_model::Container_base &	container ()
	Get the container of the object.
Object_model::Container_base const &	container () const
	Get the container of the object.

Private Attributes
friend	File
friend	Writer
shared_ptr< Object_model::Abstract >	_data
	Holds the data of the object, either an instance of Object_model::Reference for references, or an instance of Object_model::Container for direct objects.

Friends
template<typename>
bool	is_of_type (Object const &object)
	Check object type.
template<typename T>
T &	object_cast (Object &object)
	This function provides access to the value of an object.
template<typename T>
T const &	object_cast (Object const &object)
	This function provides access to the value of an object.
Object	clone (Object &object)
	Clone an object.
void	accept (Object &visitee, Visitor &v)
	Accept visitor on object.
void	accept (Object const &visitee, Visitor &v)
	Accept visitor on object.

Detailed Description

Represents a COS-file object.

The Object class represents a COS-file object.

An object can be either a direct object or an indirect object. The eight supported object types are:

• Boolean values
• Integer and real numbers
• Strings
• Names
• Arrays
• Dictionaries
• Streams
• Null (undefined)

See Section 3.2, "Objects" in the PDF-1.4 specification for further information.

Instances of Object maintain a pointer to the underlying data. Copying an object creates a new reference to the same underlying data. This is not to be confused with indirect COS objects. See the example below for clarification. Also note, that an object can only have a maximum of one owner, so adding an object to say two different arrays at the same time will result in an exception being thrown.

Todo

Describe assigning to already created objects.

using namespace Art::Paperback::Carousel;
 
// Create a direct object of array type.
//
Object object0{Array{}};
 
// Create a new direct object pointing to the same data as object0.
//
Object object1{object0};
 
// Changes made in object0 will be reflected in object1, and vice versa.
//
 
// If an identitcal copy is desired, the clone function can be used:
//
Object object2{clone(object0)};
 
// Changes made to object2 will not be reflected in object0 nor object1.
//
 
// Indirect objects work differently. Cloning an indirect object
// will clone the reference to the indirect object, not the data
// of the object.
//
 
File file;
 
// Create an indirect object of array type.
//
Object object3{file.create_object<Array>()};
 
Object object4{object3};
Object object5{clone(object3)};
 
// At this point, both object4 and object5 point to the indirect
// object first allocated in object3. This includes object5 since
// it's a clone of a reference.
//

Access to the data of an object is provided by the object_cast function, see the example below:

using namespace Art::Paperback::Carousel;
 
Object my_array{Array{}};
 
object_cast<Array>(my_array).push_back(Integer{0});

Constructor & Destructor Documentation

Object() [1/11]

Art::Paperback::Carousel::Object::Object

(

Undefined const &

undefined

)

Constructor.

This constructor creates a null (undefined) object.

Object() [2/11]

Art::Paperback::Carousel::Object::Object

(

Array

array

)

Constructor.

This constructor creates an array object.

Parameters

array

The array.

Object() [3/11]

Art::Paperback::Carousel::Object::Object

(

Boolean

boolean

)

Constructor.

This constructor creates a boolean object.

Parameters

boolean

The boolean value.

Object() [4/11]

Art::Paperback::Carousel::Object::Object

(

Dictionary

dictionary

)

Constructor.

This constructor creates a dictionary object.

Parameters

dictionary

The dictionary.

Object() [5/11]

Art::Paperback::Carousel::Object::Object

(

Integer

integer

)

Constructor.

This constructor creates an integer object.

Parameters

integer

The integer value.

Object() [6/11]

Art::Paperback::Carousel::Object::Object

(

Name

name

)

Constructor.

This constructor creates a name object.

Parameters

name

The name.

Object() [7/11]

Art::Paperback::Carousel::Object::Object

(

Real

real

)

Constructor.

This constructor creates a real object.

Parameters

real	The real value.

Object() [8/11]

Art::Paperback::Carousel::Object::Object

(

Text

text

)

Constructor.

This constructor creates a text (string) object.

Parameters

text	The text (string) value.

Object() [9/11]

Art::Paperback::Carousel::Object::Object

(

Object const &

other

)

Constructor.

Parameters

other

The object to copy from.

Object() [10/11]

Art::Paperback::Carousel::Object::Object

(

Object &&

other

)

Constructor.

This constructor makes a copy of other rather than moving from it.

This avoids the problem of having invalid-state objects.

Parameters

other

The object to move from.

Object() [11/11]

Art::Paperback::Carousel::Object::Object ( shared_ptr< Object_model::Abstract > data )

explicitprivate

Constructor.

This is an internal constructor to create an indirect object.

Member Function Documentation

attach()

void Art::Paperback::Carousel::Object::attach

(

Object_model::Owner &

owner

)

Attach object to owner.

Parameters

owner

The owner to tie this object with.

is_reference()

bool Art::Paperback::Carousel::Object::is_reference

(

)

const

Check if the objcet is a reference.

Returns

Returns true if this object is an indirect reference.

identity()

Identity const & Art::Paperback::Carousel::Object::identity

(

)

const

Get object identity, if reference.

Exceptions

Internal_error

Thrown if the object is not an indirect object.

Returns

Returns the identity of the object, if it is an indirect object.

operator=() [1/2]

Object & Art::Paperback::Carousel::Object::operator=

(

Object const &

other

)

Assignment.

Parameters

other

The object to assign from.

operator=() [2/2]

Object & Art::Paperback::Carousel::Object::operator=

(

Object &&

other

)

Assignment.

Parameters

other

The object to assign from.

operator==()

bool Art::Paperback::Carousel::Object::operator==

(

Object const &

other

)

const

Comparison.

Parameters

other

The object to compare with.

operator!=()

bool Art::Paperback::Carousel::Object::operator!=

(

Object const &

other

)

const

Comparison.

Parameters

other

The object to compare with.

container() [1/2]

Object_model::Container_base & Art::Paperback::Carousel::Object::container ( )

private

Get the container of the object.

container() [2/2]

Object_model::Container_base const & Art::Paperback::Carousel::Object::container ( ) const

private

Get the container of the object.

Friends And Related Symbol Documentation

is_of_type

template<typename>

bool is_of_type ( Object const & object )

friend

Check object type.

object_cast [1/2]

template<typename T>

T & object_cast ( Object & object )

friend

This function provides access to the value of an object.

object_cast [2/2]

template<typename T>

T const & object_cast ( Object const & object )

friend

This function provides access to the value of an object.

clone

Object clone ( Object & object )

friend

Clone an object.

Parameters

object

The object to clone.

accept [1/2]

void accept ( Object & visitee, Visitor & v )

friend

Accept visitor on object.

Parameters

visitee	The visitee.
v	The visitor.

accept [2/2]

void accept ( Object const & visitee, Visitor & v )

friend

Accept visitor on object.

Parameters

visitee	The visitee.
v	The visitor.

Member Data Documentation

_data

shared_ptr<Object_model::Abstract> Art::Paperback::Carousel::Object::_data

private

Holds the data of the object, either an instance of Object_model::Reference for references, or an instance of Object_model::Container for direct objects.