Java Reference
In-Depth Information
import
import
java.net.URL
java.net.URL
;
@Path
(
"/myservice"
)
public
public class
class
MyService
MyService
{
@GET
@Produces
(
"text/html"
)
public
public
String
get
(
@HeaderParam
(
"Referer"
)
URL referer
) {
...
}
}
The JAX-RS provider can convert the
Referer
string header into a
java.net.URL
because
this class has a constructor that takes only one
String
parameter.
This automatic conversion also works well when only a
valueOf()
method exists within the
Java type we want to convert. For instance, let's revisit the
@MatrixParam
example we used
in this chapter. In that example, we used the
@MatrixParam
annotation to inject the color of
our vehicle into a parameter of a JAX-RS method. Instead of representing color as a string,
let's define and use a Java enum class:
public
public enum
enum
Color
{
BLACK
,
BLUE
,
RED
,
WHITE
,
SILVER
}
You cannot allocate Java enums at runtime, but they do have a built-in
valueOf()
method
that the JAX-RS provider can use:
public
public class
class
CarResource
CarResource
{
@GET
@Path
(
"/{model}/{year}"
)
@Produces
(
"image/jpeg"
)
public
public
Jpeg
getPicture
(
@PathParam
(
"make"
)
String make
,
@PathParam
(
"model"
)
String model
,
@MatrixParam
(
"color"
)
Color color
) {
...
}
JAX-RS has made our lives a bit easier, as we can now work with more concrete Java objects
rather than doing string conversions ourselves.
