SetaPDF_Core_Type_Null Class representing a null object
Parses a php null value to a pdf null string and writes it into a writer.
- $writer : SetaPDF_Core_WriteInterface
- $value : null
Implementation of __sleep.
We remove the observers from all elements because they will get read if they are waked up in an observed object.
Implementation of __wakeup.
Unset the observed flag.
This method is used to clean up an object by releasing memory and references.
The observers has 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
Detach all observers from this object.
Be careful with this method!!!
Returns the main value.
This method is used for automatically resolving of indirect references.
- $forceObservation : boolean|null
Get the null value.
Checks if this object is observed.
Notifies all attached observers.
Implementation of the Observer Pattern.
Has to be called by any method that changes a value.
Converts the PDF data type to a PHP data type and returns it.