3] Run a Java or JAR file. Now when you double click on the JAR file, it will automatically run like how EXE files execute. If there is a problem with version, the file should inform you.

For those wondering how to open JNLP file without Java, you can always use Notepad. Though remember, here, you can only view the content. Also, you can use Notepad++, an open-source software that ...