Java Reference
In-Depth Information
This introductory chapter presents the deployment of Java software with a discussion of the
current pervasive state of this computing technology. At the end, some general concepts are
introduced that will form the base of the remaining topic.
The Java Runtime Environment
What is software deployment all about, and how does it apply to Java?
Generally speaking, the software deployment process is a sequence of steps as detailed in
Figure 1.1. This is a deceptive diagram because, as we will see, things are not so simple.
Software
Development
Software
Publication
Distribution
Executables
Installation
Executables
Run
F
IGURE
1.1
The software deployment lifecycle.
It could help to think of our latest favorite application that we downloaded from some Web site
and installed on our computer. Someone developed and then published it for use.
However, the scenario could be slightly different; we could have downloaded the latest
videogame to a handheld device using another form of the Internet (for example wireless pro-
tocols rather than HTTP). The installation in that case could have taken place automatically,
given the simplicity of our client device.
With the main subject of this topic, the Java platform, suddenly the two previous cases get
blurred into one, because both previous cases could have been implemented in Java. Figure 1.2
illustrates this.
