Java Reference
In-Depth Information
9.5.3. Adding structural links
Structural links in JAX-RS are instances of the
Link
class inside the entity itself. Convert-
ing them to XML or JSON then requires a special serializer, which is provided by the API.
Here'sthe
Person
class, expanded to hold the
self
,
next
,and
prev
links as attributes:
@XmlRootElement
@EqualsAndHashCode
class Person {
Long id
String first
String last
@XmlJavaTypeAdapter(JaxbAdapter)
Link prev
@XmlJavaTypeAdapter(JaxbAdapter)
Link self
@XmlJavaTypeAdapter(JaxbAdapter)
Link next
}
The
prev
,
self
, and
next
links are instances of the
javax.ws.rs.core.Link
class, as before.
Link.JaxbAdapter
is an inner class that tells JAXB how to serialize
the links.
Setting the values of the link references is done in the resource, this time using an interest-
ing Groovy mechanism:
Response findById(@PathParam("id") long id) {
Person p = dao.findById(id)
getLinks(id).each { link ->
p."${link.rel}" = link
}
}
The same
getLinks
private method is used as in the headers section, but this time the
links are added to the
Person
instance. By calling
link.rel
(which calls the
getRel
method) and injecting the result into a string, the effect is to call
p.self
,
p.next
, or
