Hudson CI, or the new fork Jenkins CI, is a Java web server application to automate and control the building of projects.
Hudson is very similar to Jenkins, and they differ only in the sense of licensing policies, hosting, and some minimal functionalities; some authors work with both systems, but in this book, we will refer only to Hudson.
You can download Hudson (formally known as Hudson Open Source Continuous Integration Server from the Eclipse Foundation) from http://eclipse.org/hudson/download.php.
The next step is to launch the embedded Jetty servlet container:
$ java -jar Hudson.<version>.war
Jenkins can be downloaded from http://mirrors.jenkins-ci.org/war/latest/jenkins.war ...