Developing using Eclipse
If you are developing new features in CAS, or just plan on bringing the project into Eclipse, the development team recommends using the m2eclipse plugin which can read the POM files and manage the dependencies for you on the classpath.
Please follow the directions on the m2eclipse web site on how to install and enable the plugin.
Developing using IntelliJ
IntelliJ has built in support for loading a project based on the POM file. When opening a project, please choose the cas3 pom.xml as the file to open.