Integration - eXist: A NoSQL Database and Application Development Platform - page 340

Client
The Client object manages the underlying connection to the HTTP Server and
any configuration required for that connection. The Client also allows you to
construct WebResource objects. As it is mostly likely that we will want to
authenticate with eXist when we manipulate resources via the REST Server API,
we will actually make use of the Apache HTTP client integration for Jersey, as
this allows us to provide authentication credentials. See Example 13-6 .
Example 13-6. Constructing a suitable Client object for communicating with eXist
using Jersey
//set up authentication
final CredentialsProvider credentialsProvider = new BasicCredentialsProvider ();
credentialsProvider . setCredentials ( AuthScope . ANY ,
new UsernamePasswordCredentials ( "admin" , "my-admin-password" ));
final DefaultApacheHttpClient4Config config =
new DefaultApacheHttpClient4Config ();
config . getProperties (). put (
ApacheHttpClient4Config . PROPERTY_CREDENTIALS_PROVIDER , credentialsProvider );
//construct the client
final Client client = ApacheHttpClient4 . create ( config );
WebResource
A WebResource object indicates a resource on the REST Server (although it may
not exist yet) that is addressable by a URI. You may construct as many WebRe
source objects as you wish from a single client; you then perform actions on
these resources, such as PUT or GET . See Example 13-7 .
Example 13-7. Constructing a Jersey WebResource object for communicating with
eXist
final String uri = "http://localhost:8080/exist/rest/db/some-document.xml" ;
final WebResource resource = client . resource ( uri );
ClientResponse
Once you have a WebResource object, you can make a request to the server. Jersey
offers some easy-to-use facilities to allow you to serialize/deserialize Java objects
for the request/response as XML using JAXB . However, to keep things simple, we
will just consider the raw response object that Jersey can provide from any
request: the ClientResponse . The ClientResponse object allows you access to all
of the HTTP responses sent from the REST Server, including all headers and
bodies. See Example 13-8 .