In this chapter we will create and deploy a simple portlet using the Plugins SDK. It will allow a customized greeting to be saved in the portlet's preferences, and then display it whenever the portlet is viewed. Finally we will add friendly URL mapping to the portlet to clean up its URLs.
In developing your own portlets you are free to use any framework you prefer, such as Struts, Spring MVC, or JSF. For this portlet we will use the Liferay MVCPortlet framework as it is simple, lightweight, and easy to understand.
Additionally, Liferay allows for the consuming of PHP and Ruby applications as portlets, so you do not need to be a Java developer in order to take advantage of Liferay's built-in features (such as user management, communities, page building and content management). You can use the Plugins SDK to deploy your PHP or Ruby application as a portlet, and it will run seamlessly inside of Liferay. There are plenty of examples of this; to see them, check out the directory plugins/trunk from Liferay's public Subversion repository.