Opens an existing document.
public Document( Stream stream )
The document should have no open password set.
This method gives you full control how the document is read. It requires that the stream remains open during the lifetime of the document.
Provided that the argument stream is seekable, information will be read from the PDF file on demand. E.g. if one hits page 10 , we seek to the correct position, skipping all other pages, and we return page 10. When after that one request say page 5 we seek back and read that page. This means that one should not close/dispose the stream during the hole session one needs the document, or pages, bookmarks, info extracted from it.
If the stream is not seekable, we will read information eagerly, i.e. the entire document will first be read into memory before we access it.