By default, the Web Start sandbox blocks access to the file system through conventional java.io access mechanisms; however, by requiring user interaction for every read and write, the FileOpenService ...
Java Web Start allows you to deploy full-featured applications using your Web browser, bypassing complex installation procedures. See if Web Start is right for your build and deployment process. In ...
Since JNLP files are simply Java Web Start files that open applications through an Internet browser, any browser that works in Windows 8.1 will open a JNLP file as long as you have Java installed.