Book Image

Groovy 2 Cookbook

Book Image

Groovy 2 Cookbook

Overview of this book

Get up to speed with Groovy, a language for the Java Virtual Machine (JVM) that integrates features of both object-oriented and functional programming. This book will show you the powerful features of Groovy 2 applied to real-world scenarios and how the dynamic nature of the language makes it very simple to tackle problems that would otherwise require hours or days of research and implementation. Groovy 2 Cookbook contains a vast number of recipes covering many facets of today's programming landscape. From language-specific topics such as closures and metaprogramming, to more advanced applications of Groovy flexibility such as DSL and testing techniques, this book gives you quick solutions to everyday problems. The recipes in this book start from the basics of installing Groovy and running your first scripts and continue with progressively more advanced examples that will help you to take advantage of the language's amazing features. Packed with hundreds of tried-and-true Groovy recipes, Groovy 2 Cookbook includes code segments covering many specialized APIs to work with files and collections, manipulate XML, work with REST services and JSON, create asynchronous tasks, and more. But Groovy does more than just ease traditional Java development: it brings modern programming features to the Java platform like closures, duck-typing, and metaprogramming. In this new book, you'll find code examples that you can use in your projects right away along with a discussion about how and why the solution works. Focusing on what's useful and tricky, Groovy 2 Cookbook offers a wealth of useful code for all Java and Groovy programmers, not just advanced practitioners.
Table of Contents (17 chapters)
Groovy 2 Cookbook
About the Authors
About the Reviewers

Consuming RSS and Atom feeds

RSS feeds and Atom feeds are a standardized way to distribute headlines and updates from websites and blogs. Both RSS and Atom feeds are XML documents. RSS is older but widely popular, while Atom is newer and has several advantages over RSS, chiefly the namespace support.

For the main differences between Atom and RSS, check the Wikipedia entry about RSS: Both formats are largely supported, and often blogs and sites output headline feeds in RSS and Atom at the same time.

In this recipe, we are going to cover the basics of RSS and Atom feed parsing with Groovy.

Getting ready

As RSS and Atom feeds are XML based, it's easy to parse them using one of the several tools offered by Groovy (see the Reading XML using XmlParser recipe in Chapter 5, Working with XML in Groovy).

We will show how to detect if a feed is RSS or Atom and parse it accordingly.

How to do it...

We will create a FeedParser class which will contain the code to open a URL...