If you want to easily call a REST web services as the ones we describe in the article entitled "RESTful webservices running on JBoss", you may use Resteasy. Be very careful when you use it because we noticed that the default behaviour of Resteasy does not correctly close the connections (we experienced the issues with resteasy-jaxrs/2.0-beta-2).
We used to write the following code:
ClientResponse<String> response = null;
ClientRequest request = new ClientRequest("http://monurl");
request.queryParameter(idName, id);
response = request.get(String.class);
 ClientRequest uses an executor to obtain the response. Without any parameter, a new executor is created for each new request and the connections are not automatically closed. A proposed fix is to use a unique executor that you can defined like this:
private static final ClientExecutor CLIENT_EXECUTOR = new ApacheHttpClientExecutor(new HttpClient(new MultiThreadedHttpConnectionManager()));
[...]
ClientRequest request = new ClientRequest("http://monurl", CLIENT_EXECUTOR);
Internally, ApacheHttpClientExecutor will reuse the same HttpClient for each request with an automatic connection pool.