This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
The book has many code examples and all the code in the book can be downloaded from the publisher site. I don't use any specific IDE in the book (or in my day job) but there is a section in the appendix that discusses the Grails support in the three major IDEs.
I don't cover Grails/Spring integration beyond what Grails already includes. Integrating existing Spring components with Grails is pretty easy to do but didn't really fit the scope of the book.