The Java Development Kit will serve as our middleware package and is a prerequisite for the Greenfoot development software. Note that middleware differs from plugins, in that, middleware is typically required to make another program run while a plugin is used to enhance the abilities of another application (for example, Adobe Flash would be a plugin for Internet Explorer).
To complete these steps, you will need to have completed the first recipe of Chapter 3, Sequencing Applications, where you created a virtual machine to capture App-V packages.