23.4.6. Testing resources and providers

Seam includes a unit testing utility class that helps you create unit tests for a RESTful architecture. Extend the SeamTest class as usual and use the ResourceRequestEnvironment.ResourceRequest to emulate HTTP requests/response cycles: 
import org.jboss.seam.mock.ResourceRequestEnvironment;
import org.jboss.seam.mock.EnhancedMockHttpServletRequest;
import org.jboss.seam.mock.EnhancedMockHttpServletResponse;
import static org.jboss.seam.mock.ResourceRequestEnvironment.ResourceRequest;
import static org.jboss.seam.mock.ResourceRequestEnvironment.Method;

public class MyTest extends SeamTest {

   ResourceRequestEnvironment sharedEnvironment;

   @BeforeClass
   public void prepareSharedEnvironment() throws Exception {
       sharedEnvironment = new ResourceRequestEnvironment(this) {
            @Override
            public Map<String, Object> getDefaultHeaders() {
               return new HashMap<String, Object>() {{
                   put("Accept", "text/plain");
               }};
            }
         };
   }

   @Test
   public void test() throws Exception
   {
      //Not shared: new ResourceRequest(new ResourceRequestEnvironment(this), Method.GET, "/my/relative/uri)

      new ResourceRequest(sharedEnvironment, Method.GET, "/my/relative/uri)
      {
         @Override
         protected void prepareRequest(EnhancedMockHttpServletRequest request)
         {
            request.addQueryParameter("foo", "123");
            request.addHeader("Accept-Language", "en_US, de");
         }

         @Override
         protected void onResponse(EnhancedMockHttpServletResponse response)
         {
            assert response.getStatus() == 200;
            assert response.getContentAsString().equals("foobar");
         }

      }.run();
   }
}
This test only executes local calls, it does not communicate with the SeamResourceServlet through TCP. The mock request is passed through the Seam servlet and filters and the response is then available for test assertions. Overriding the getDefaultHeaders() method in a shared instance of ResourceRequestEnvironment allows you to set request headers for every test method in the test class.
Note that a ResourceRequest has to be executed in a @Test method or in a @BeforeMethod callback. You can not execute it in any other callback, such as @BeforeClass.