Head over to Leanpub to grab a PDF version of this book
This book covers the nitty gritty of JAX-RS: a Java based standard (specification) for building RESTful web services. It helps you speak HTTP (the language of the web) using Java.
The contents of this book are divided into distinct sections which cover the bare basics, core components and some of the advanced framework features as well. Here is a snapshot
It covers JAX-RS 2.0 (the latest version) and can be used as a cheat sheet or a getting started with JAX-RS style guide.