the instance of a Outline object which comes to the parent of the created outline object. If null, the outline is created as a root outline.
the caption of the outline object.
the instance of a Encoding object applied to the title. If null, PDFDocEncoding is used.
when createOutline() succeeds, it returns a instance of Outline object. Otherwise, it returns null and error-handler is invoked.
Creates an instance of Outline object.