Client-Server Web Apps with JavaScript and Java

Chapter 11. Packaging and Deployment

The thought occurred to me, as I waited around that day, that it would be easier to lift my trailer up and, without any of its contents being touched, put it on the ship.

—Malcom McLean

Malcom McLean had an idea in 1937 that would lead to his legacy as the “the father of containerization.” It came to him while waiting in Hoboken for cotton bales he had delivered to be loaded for transport overseas. It wasn’t until 1956 that McLean developed the metal shipping container, which greatly simplified cargo handling and revolutionized the shipping industry. Innovations in packaging lead to efficiencies in shipping. In technology, deployment and distribution of applications is analogous to shipping. Java provides standardized packaging, which is foundational to the distribution of code and deployment of applications.

Java and JEE Packaging

Java packaging formats are fundamental building blocks in JEE applications. They are also used in more recent deployment processes that do not adhere strictly to the JEE specification.

Java developers initially develop code outside of deployment packages. A Java class corresponds with a file on the operating system. Confusingly enough, a Java package is not really related to packaging but instead is a namespace that reflects the path from an application root to a directory where a class resides. It is rare to encounter classes and packages on their own outside of a programmer’s development environment. An application or ...