The Java virtual machine (JVM) is a program whose sole purpose is to execute other programs. This simple idea has made Java one of the most successful and long-lived platforms of all time.

Latest release of the JVM language also features hundreds of new and improved extension methods including 10x faster arrays.

“Jeffing,” named after Olympian and author Jeff Galloway, is a kind of lower-key fartlek (another 10/10 name). If both of ...