Index

  1. \setasign\SetaPDF2
    1. Core
      1. Type
        1. AbstractType
        2. BypassSecHandlerInterface
        3. Dictionary
        4. Exception
        5. IndirectObjectInterface
        6. IndirectReference
        7. OwnerInterface
        8. PdfArray
        9. PdfBoolean
        10. PdfCallback
        11. PdfDictionary
        12. PdfHexString
        13. PdfIndirectObject
        14. PdfIndirectReference
        15. PdfName
        16. PdfNull
        17. PdfNumeric
        18. PdfObjectStream
        19. PdfRaw
        20. PdfScalarValueInterface
        21. PdfStream
        22. PdfString
        23. PdfStringInterface
        24. PdfToken

setasign\SetaPDF2\Core\Type

PdfNull Class representing a null object

File: /SetaPDF v2/Core/Type/PdfNull.php
Old class name (alias): \SetaPDF_Core_Type_Null

Class hierarchy

Implements

Summary

Static Methods

Static Properties

Methods

Properties

Static Properties

$_instance

static protected \SetaPDF_Core_Type_Null PdfNull::$_instance

Properties

$_observed

protected bool AbstractType::$_observed = false

Defines if this object is under observation

$_observers

protected array 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.

$metadata

public array AbstractType::$metadata = array()

An array for individual metadata.


Static Methods

_ensureType()

protected static 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 Exception

ensureType()

public static AbstractType::ensureType (
mixed $value
): self

Ensures that the passed value is a AbstractType instance.

Parameters
$value : mixed
 
Exceptions

Throws Exception

ensureWithType()

public static AbstractType::ensureWithType (
string $type,
mixed $value
): \SetaPDF_Core_Type_AbstractType

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

Parameters
$type : string
 
$value : mixed
 
Exceptions

Throws Exception

getInstance()

public static PdfNull::getInstance (
void
): \SetaPDF_Core_Type_Null

Get a singleton instance of this class.

is()

public static 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 PdfNull::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()

public AbstractType::__construct (
void
)

The constructor.

__clone()

public PdfNull::__clone (
void
): void

Implementation of __clone().

__sleep()

public 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()

public AbstractType::__wakeup (
void
): void

Implementation of __wakeup.

Unset the observed flag.

attach()

public PdfNull::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()

public AbstractType::cleanUp (
void
): void

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()

public AbstractType::deepClone (): \SetaPDF_Core_Type_AbstractType

Clone the object recursively in the context of a document.

Parameters
$document : \SetaPDF_Core_Document
 

detach()

public AbstractType::detach (
\SplObserver $observer
): void

Detach an observer from the object.

Implementation of the Observer Pattern.

Parameters
$observer : \SplObserver
 

detachAll()

public AbstractType::detachAll (
void
): void

Detach all observers from this object.

Be careful with this method!!!

ensure()

public AbstractType::ensure (
?bool $forceObservation = null,
array &$ensuredObjectsList = array ( )
): \SetaPDF_Core_Type_AbstractType

Returns the main value.

This method is used for automatically resolving of indirect references.

Parameters
$forceObservation : ?bool
 
$ensuredObjectsList : array

A list of all ensured indirect objects to prevent recursion

getValue()

public PdfNull::getValue (
void
): null

Get the null value.

See

isObserved()

public AbstractType::isObserved (
void
): bool

Checks if this object is observed.

notify()

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

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

Parameters
$value : null
 
Exceptions

Throws Exception

See

toPdfString()

public PdfNull::toPdfString (
?\SetaPDF_Core_Document $pdfDocument = null
): string

Returns the type as a formatted PDF string.

Parameters
$pdfDocument : ?\SetaPDF_Core_Document
 

toPhp()

public PdfNull::toPhp (
void
): null

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

writeTo()

public PdfNull::writeTo (
\SetaPDF_Core_Document $pdfDocument
): void

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

Parameters
$pdfDocument : \SetaPDF_Core_Document
 

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