It looks as if you are reading the PDF file from your current working
directory (that is, the folder that your program is launched from). By
that logic, you should be able to open a PDF stored anywhere by entering
it's full path, rather than just the file name. For instance:
String filePath = "C:UsersyouDesktopaleemullah resume.pdf"
Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " +
filePath variable to wherever you are storing
the PDF file.
You might also consider using a JFileChooser to select the file if you want the user to
choose the PDF during runtime. Check out this example of how to open a dialog box from Java to
pick a PDF file and retrieve its path.