Java Reference
In-Depth Information
@Path
(
"roy&fielding"
)
public
public
String
getOurBestCustomer
() {
...
}
}
The
@Path
expression for
getOurBestCustomer()
would match incoming requests like
GET
/customers/roy%26fielding
.
Matrix Parameters
One part of the URI specification that we have not touched on yet is
matrix parameters
. Mat-
rix parameters are name-value pairs embedded within the path of a URI string. For example:
http:
//example.cars.com/mercedes/e55
;
color
=
black
/
2006
They come after a URI segment and are delimited by the “;” character. The matrix parameter
in this example comes after the URI segment
e55
. Its name is
color
and its value is
black
.
Matrix parameters are different than query parameters, as they represent attributes of certain
segments of the URI and are used for identification purposes. Think of them as adjectives.
Query parameters, on the other hand, always come at the end of the URI and always pertain
to the full resource you are referencing.
Matrix parameters are ignored when matching incoming requests to JAX-RS resource meth-
ods. It is actually illegal to specify matrix parameters within an
@Path
expression. For ex-
ample:
@Path
(
"/mercedes"
)
public
public class
class
MercedesService
MercedesService
{
@GET
@Path
(
"/e55/{year}"
)
@Produces
(
"image/jpeg"
)
public
public
Jpeg
getE55Picture
(
@PathParam
(
"year"
)
String year
) {
...
}
If we queried our JAX-RS service with
GET /mercedes/e55;color=black/2006
, the
getE55Picture()
method would match the incoming request and would be invoked. Matrix
parameters are not considered part of the matching process because they are usually variable
attributes of the request. We'll see in
Chapter 5
how to access matrix parameter information
within our JAX-RS resource methods.
