Beginning Groovy and Grails
Beginning Groovy and Grails: From Novice to Professional (Beginning from Novice to Professional)
Authors: Christopher M. Judd, Joseph Faisal Nusairat, and Jim Shingler
Amazon info
Having been very interested in Ruby on Rails - but finding Ruby impenetrable, I figured Groovy/Grails would be a better fit, so I picked up this book. Good introduction to the topic, with a nice example that one can build and follow along. First three chapters are on Groovy and then it shifts to Grails. I know that I will need to get a reference book to do real work, but I was able to read this cover-to-cover to get a good overview of what is possible and how I should approach my first Grails project.
One related topic. In the past, I have written about how much I like Hibernate and how it just feels like the right way to handle ORM mapping. On the other hand, I read about Spring and didn't see the benefit over current alternatives (I especially disliked the xml bean configurations). Now we come to Grails. Like Hibernate (which Grails uses) this feels right and feels like it can be a real productivity enhancer. At times I was simply amazed at how easy and fast things were (sure, I am not thrilled about the inability of the Groovy compiler to catch typos) - but sometimes it seems like magic. And it has even redeemed Spring in my mind - because Grails is built on Spring and if Spring allows one to build things like Grails, then Spring must be pretty awesome (obviously, I will never be a hard core server side hacker).
Recommended: To all Grails n00bs, with the recognition that more is needed.