IntelliJ IDEA is one of the most powerful Java IDEs. One of its major strengths is the flexibility of configuration; IntellJ can be integrated into different project organizations and structures. Therefore, IntelliJ can work with Liferay Portal source in several ways.

First, there is a project structure. Liferay Portal project may be organized in one single module, where all sources are 'joined' together as they are in the single source folder and all share the same libraries. This approach is easier to configure, but user has to be aware of code dependencies. On the other hand, project can be split in several modules, where each IntelliJ module matches Portals module. This configuration is obviously a bit more complex, however it reflects the real nature of the project.

Once when project is configured, it will be ready for building. IntelliJ can be configured to compile sources to the same output folders as Ant script does, or to use other folder (what is more IntelliJ way).

Again, user has several options how to run Liferay Portal on Tomcat (or some other container). Liferays Tomcat can be started outside of IntelliJ and then attached to it - it is easiest to configure, but gives less control. Liferays Tomcat may be started directly from Idea, what gives more control and is more IntelliJ way to do it. Even here user has opportunity to deploy portal manually (using Ant script) or to let IntelliJ to deploy it - second approach gives even more control to the user.

Following child pages explains several approaches of using IntelliJ with Liferay Portal source.