Before we create any artifacts, let us first learn a bit about Apache Jelly and how it is used within the ServiceNow platform.
Note
Basic knowledge of XML is important for this chapter. Apache Jelly follows XML syntax, and thus any developer with prior knowledge of XML, HTML, XHTML, or JavaScript should be able to learn it quickly. The project homepage is located at http://commons.apache.org/proper/commons-jelly/.
In the ServiceNow platform, Apache's Jelly syntax is used to render forms, lists, UI pages, and other elements in the browser. Jelly script is comprised of XML and HTML code. Jelly brings in its own set of XML tags, known as Jelly tags, using a specific XML namespace. ServiceNow has also implemented some extension to Jelly tags, referred to as Glide tags. The Jelly scripting is only used in UI macros and UI pages that run on the server. The Jelly code, which is mostly XML code, converts to HTML before it is sent to the browser.