SetaPDF_Core_Type_Null Class representing a null object

File: /SetaPDF v2/Core/Type/Null.php

Class hierarchy

Implements

Summary

Static Properties


Properties

$_observed

Defines if this object is under observation

$_observers

protected array SetaPDF_Core_Type_AbstractType::$_observers = array()

The Objects to notify on any change

This will be the PDF document or another value holding this one. Initially this will be an array.


Static Methods

_ensureType()

protected static SetaPDF_Core_Type_AbstractType::_ensureType (
string $type, mixed $value, string $errorMessage [, $ensure = true ]
): mixed

Ensure that a value is an instance of a specific PDF type.

Parameters
$type : string
 
$value : mixed
 
$errorMessage : string
 
$ensure
 
Exceptions

Throws SetaPDF_Core_Type_Exception

ensureType()

Ensures that the passed value is a SetaPDF_Core_Type_AbstractType instance.

Parameters
$value : mixed
 
Exceptions

Throws SetaPDF_Core_Type_Exception

ensureWithType()

Ensures that the passed value is an instance of the passed type.

Parameters
$type : string
 
$value : mixed
 
Exceptions

Throws SetaPDF_Core_Type_Exception

getInstance()

Get a singleton instance of this class.

is()

public static SetaPDF_Core_Type_AbstractType::is (
string $type, mixed $value [, bool $ensure = true ]
): bool

Checks if the type of a value is the expected one.

Indirect references will be evaluated if $ensure is set to true.

Parameters
$type : string
 
$value : mixed
 
$ensure : bool
 

writePdfString()

public static SetaPDF_Core_Type_Null::writePdfString (
SetaPDF_Core_WriteInterface $writer, null $value
): void

Parses a php null value to a pdf null string and writes it into a writer.

Parameters
$writer : SetaPDF_Core_WriteInterface
 
$value : null
 
Exceptions

Throws InvalidArgumentException

See

Methods

__construct()

The constructor.

__clone()

public SetaPDF_Core_Type_Null::__clone (
void
): void

Implementation of __clone().

__sleep()

public SetaPDF_Core_Type_AbstractType::__sleep (
void
): array

Implementation of __sleep.

We remove the observers from all elements because they will get read if they are waked up in an observed object.

__wakeup()

Implementation of __wakeup.

Unset the observed flag.

attach()

public SetaPDF_Core_Type_Null::attach (
SplObserver $observer
): void

Add an observer to the object (will never be called by a NULL object).

Implementation of the Observer Pattern.

Parameters
$observer : SplObserver
 

cleanUp()

This method is used to clean up an object by releasing memory and references.

The observers have to be removed with the "detach()"-method. Only if there is no observer left this method should really release resources.

The method has to be implemented by each object type

deepClone()

Clone the object recursively in the context of a document.

Parameters
$document : SetaPDF_Core_Document
 

detach()

Detach an observer from the object.

Implementation of the Observer Pattern.

Parameters
$observer : SplObserver
 

detachAll()

Detach all observers from this object.

Be careful with this method!!!

ensure()

public SetaPDF_Core_Type_AbstractType::ensure (
[ bool|null $forceObservation = null ]
): SetaPDF_Core_Type_AbstractType

Returns the main value.

This method is used for automatically resolving of indirect references.

Parameters
$forceObservation : bool|null
 

getValue()

isObserved()

Checks if this object is observed.

notify()

public SetaPDF_Core_Type_AbstractType::notify (
void
): void

Notifies all attached observers.

Implementation of the Observer Pattern.

Has to be called by any method that changes a value.

setValue()

public SetaPDF_Core_Type_Null::setValue (
null $value
): void

Implementation of the abstract setValue() method which is useless for this object type.

Parameters
$value : null
 
Exceptions

Throws SetaPDF_Core_Type_Exception

See

toPdfString()

public SetaPDF_Core_Type_Null::toPdfString (
[ SetaPDF_Core_Document|null $pdfDocument = null ]
): string

Returns the type as a formatted PDF string.

Parameters
$pdfDocument : SetaPDF_Core_Document|null
 

toPhp()

public SetaPDF_Core_Type_Null::toPhp (
void
): null

Converts the PDF data type to a PHP data type and returns it.

writeTo()

Writes the type as a formatted PDF string to the document.

Parameters
$pdfDocument : SetaPDF_Core_Document