Cannot open pdf from a remote url

I am using the version 5.1.0_27 of icepdf and have two basic jar files of icepdf-core and icepdf-viewer. When I open file from local machine, it openes fine. But when I put a remote url on the filepath, I get this error:
Code:

ICEpdf could not open the specified file at http://www.icepdf.org/resources/DevelopersGuide.pdf. 
 The file may be corrupted or not a supported file type.

.
The file in question is http://www.icepdf.org/resources/DevelopersGuide.pdf.

Can you guide me on this error. I am fairly new to this product of yours and I am also not using maven and gradle.

Thank you.

Hi,

Are you trying to open the http://www.icepdf.org/resources/DevelopersGuide.pdf URL? That file is no longer available on the icepdf.org site.

You should try opening a different PDF URL.