Liferay's developers use a variety of tools to develop the product and as a consequence of that they have always tried hard to allow other developers to use any tools they wanted for their own development. Because of this you can develop portals based on Liferay with complex IDEs Eclipse, Netbeans or IntelliJ Idea or just use text editors such as Notepad. You can write your persistence layer directly using SQL and JDBC or you can use advanced object-relational mapping libraries such as hibernate or iBatis.
But while being agnostic is great, specially for more experienced developers who can reuse their existing knowledge, it can be overwhelming for newcomers. For that reason Liferay has also develped specific development tools that can be used to ease the learning curve when developing portlets with Liferay. The most significant of these tools is Liferay IDE, a fully featured Integrated Development Environment based on Eclipse.
Liferay IDE is an extension for the Eclipse platform that supports development of plugin projects for the Liferay Portal platform. It is available as a set of Eclipse plugins installable from an update-site. The latest version supports developing 5 Liferay plugin types: portlets, hooks, layout templates, themes, and ext plugins. Liferay IDE requires the Eclipse Java EE developer package using either Galileo or Helios versions.
The first two sections below show how to install and set-up Liferay IDE within your environment. If you are using a copy of Liferay Developer Studio, which comes with Liferay Portal Enterprise Edition, you can skip directly to the section titled "Testing the Liferay portal server" since it comes already preconfigured.