Programming Groovy: Dynamic Productivity for the Java Developer (Pragmatic Programmers)

Venkat does a fantastic job of explaining what Groovy is, how it evolved, why you would want to use it, and how to integrate it with your Java projects.He has a fantastic sense of humor, which really shows through in this book. If you ever get the opportunity to see him speak, take it. He's an incredibly intelligent, articulate programmer, and probably the most language-agnostic programmer I've ever met.One caveat: if you are a Java zealot, this book may send you into little fits. In the first section of the book, he converts standard Java code (groovyc can compile most Java code, so it's actually Groovy code that looks like Java) into Groovy. There are a lot of comments that may make Java zealots throw little fits.If you're stuck using Java, get this book.

I am still fairly new to Groovy, but I have been experimenting with Groovy for about a year. This book, so far, has really helped me grasp some of the more complex concepts of Groovy and dynamic scripting languages in general. I am big fan of this book and strongly recommend it to anyone who is interested in Groovy and to any Java developer who wants an incredibly extensible tool set in his/her back pocket.

This book does a solid job of outlining the features of Groovy and how to use them. But I am not sure it adds too much more than is available in the online documentation for Groovy. I was looking for more in depth case studies and advice on how to integrate Groovy in the enterprise and existing projects. Scripted, dynamic Java would be very useful as both a debugging tool "in the wild", and as an on-the-fly configuration tool, but I didn't see enough information around those topics in this book. That said, the chapter on using Groovy for unit-testing Java with mock objects is very helpful.The main thrust of this book is using Groovy as a standalone lightweight app development tool that is Java-like, but with features that Java doesn't have like closures etc. This is all well and good, but if coding from scratch in a dynamic language why not use Ruby, Python etc? Hell, why not just use JavaScript on Rhino?? :-) If restricted by the JVM, then JRuby etc. Anyway, I digress, but I figured there would be a lot more information on integration of Groovy in to your current Java projects and frameworks, not building projects from scratch in Groovy. It does tell you the basics of integration, but when buying a book to flesh out the online docs, you expect a fairly significant case study or example for each key feature.In summary, I'm slightly underwhelmed by this book in the light of the pretty good online docs for Groovy. I must admit, however, I have not studied the last section on DSLs yet, which may yet reveal some nuggets of gold.

I started using Groovy a year and a half ago, for personal projects. I enjoy the language and find it refreshing. The first part of the book is very useful as a "quick reference" for some of the core aspects of the language with the bonus of added explanation, examples and comparisons with Java.The second part of the book is a little more advanced or perhaps simply a little more specialized in its content, but still contains useful information.It's a book I will refer to time and time again.

Groovy is an interesting and valuable addition to the JVM family of languages. Unfortunately, the author of this book, while he may know groovy, knows little about writing. The book wanders between shining generalities about the wonders of groovy, snarky but empty snipes at Java, and way too much of the author trying to prove how clever he is. Any tech book where you read as much about the author as the subject is a bad one. And this definitely qualifies.In and around all that he does manage to impart some useful knowledge of groovy. However the descriptions and explanations of code are often too brief, telling you what the code does but leaving the reader to puzzle through how it does it. Had the author spent less time telling us about himself and feeding us meaningless propaganda, perhaps he would have had more room to properly teach.

Overall, a very good book on Groovy. Great simple examples to work from. I was very impressed with the chapter on Closures which can be a difficult subject for those coming from primarily a Java background. Wanna learn Groovy? Get this book. [...]

def helped me move forward with my job

When a new language comes out, the first set of books focuses on either the shiny new, golly-gee-wow features of the language or on how to use it to get real work done. But eventually someone comes out with a book that no longer treats the new language like a shiny new thing, but as a serious contender in the language universe. And that's Programming Groovy does (disclaimer: I know Venkat). It doesn't treat Groovy like a novelty act. It also doesn't provide recipes. Instead, it treats Groovy as a real programming language. I'll have to admit, this is the Groovy book for which I've been waiting.Groovy is friendlier syntax for programming Java (I called it the real JDK in a recent blog posting). Books about the practical aspects of Groovy are very important because, as a language, it resides in a unique place: it's a low impedance way to program the Java platform, and it displaces Java for lots of common tasks. But it is also a powerful language in its own right. Programming Groovy has 4 chapters on meta-programming Groovy, and another long chapter on building domain specific languages. That's meaty stuff. It never condescends or makes excuses for Groovy but treats it like a real language. This book goes in depth into places in Groovy where it's hard to find information online, like how ExpandoMetaclass really works. This is both the most comprehensive and authoritative book on the Groovy language around. This is going to be a classic in the Groovy literature and an exemplar for describing new languages.