About Tomasz Nurkiewicz   WADL in Java: Gentle introduction
WADL (Web Application Description Language) is to REST what WSDL
is to SOAP. The mere existence of this language causes a lot of
controversy (see: Do we need WADL? and To WADL or not to WADL).
I can think of few legitimate use cases for using WADL, but if
you are here already, you are probably not seeking for yet
another discussion. So let us move forward to the WADL itself.
In principle WADL is similar to WSDL, but the structure of the
language is much different. Whilst WSDL defines a flat list of
messages and operations either consuming or producing some of
them, WADL emphasizes the hierarchical nature of RESTful web
services. In REST, the primary artifact is the resource. Each
resource (noun) is represented as an URI. Every resource can
define both CRUD operations (verbs, implemented as HTTP methods)
and nested resources. The nested resource has a strong
relationship with a parent resource, typically representing an
ownership.  A simple example