About Gregor Riegler
In this post i want to dig into spring mvc a little, revealing what happens behind the scenes when a request is converted to your parameter object and vice versa. Before we start, i want to explain the purpose of these annotations.
What are @RequestBody and @ResponseBody for?
They are annotations of the spring mvc framework and can be used in a controller to implement smart object serialization and deserialization. They help you avoid boilerplate code by extracting the logic of messageconversion and making it an aspect. Other than that they help you support multiple formats for a single REST resource without duplication of code. If you annotate a method with @ResponseBody, spring will try to convert its return value and write it to the http response automatically. If you annotate a methods parameter with @RequestBody, spring will try to convert the content of the incoming request body to your parameter object on the fly.
Here is an example
Source : http://www.javacodegeeks.com/2013/07/spring-mvc-requestbody-and-responsebody-demystified.html
