The current release of Beam Four Java Edition requires Java 1.8.0 or higher be installed on your computer. To verify it, open a command window and enter...
java -version
Your Java run-time will respond with something like "1.8.0_20". Then close your command window.
If you are running an older version of Java, it is time to update that to the newer secure version.
LINUX users: most distros require that you set the .jar file properties to make it runnable. To do this, right click the .jar icon, choose Properties/General "Open with JDK" and if available "Set as Default." Then on Permissions tab, click "Make the file executable."
