public function getSize()
 {
     return $this->_dataSource->getSize();
 }
 /**
  * Object constructor.
  *
  * Verifies that the data source has been properly initialized.
  *
  * @param Zend_Pdf_FileParserDataSource $dataSource
  * @throws Zend_Pdf_Exception
  */
 public function __construct(Zend_Pdf_FileParserDataSource $dataSource)
 {
     if ($dataSource->getSize() == 0) {
         throw new Zend_Pdf_Exception('The data source has not been properly initialized', Zend_Pdf_Exception::BAD_DATA_SOURCE);
     }
     $this->_dataSource = $dataSource;
 }