In this chapter, we will cover some more advanced Groovy features. Coincidentally, these are also the features that, along with closures, allow us to extend and manipulate the language in order to create DSLs. We will cover a lot of ground in this chapter, including the following important features:
Named parameters: To begin, we will look at this simple but effective feature, and see how maps passed as parameters act as named parameters to a method.
Command chains: We will cover how, when chaining methods together, we can omit the dot notation to give us a simple command chain DSL pattern.
Builders: We will cover how to use Groovy builders to rapidly construct anything from web pages and XML to Swing UIs. While looking at Groovy builders, we will also introduce the native Groovy support for tree-based DOM structures, by looking at the built-in
GPathoperators in the Groovy language.SwingBuilder: We will add a quick and simple UI to our Twitter DSL,...