Tom Snyder's first foray into RPG programming books, Advanced Integrated RPG, is an auspicious beginning. The book is ostensibly about three specific examples of integration between RPG and Java: accessing Excel spreadsheets, creating PDF documents, and sending email. And while the book presents these topics quite well, it's the larger view of the book that really makes it special.
 
To properly take advantage of the Java capabilities of RPG, you must use the Integrated Language Environment (ILE) version of RPG. Since not all of us are ILE experts, a book introducing the integration of Java and RPG should by necessity cover the concepts of ILE, especially as they apply to using the two languages together. And while that makes a lot of theoretical sense, practically speaking, a thorough treatise on ILE programming would be larger than this book's 400 pages.