GrizzlyResourceTest.java

import java.util.List;
import java.util.Set;

import javax.servlet.http.HttpServletRequest;

import org.codehaus.jackson.map.Module;
import org.junit.After;
import org.junit.Before;

import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.config.ClientConfig;
import com.sun.jersey.api.client.config.DefaultClientConfig;
import com.sun.jersey.api.core.ResourceConfig;
import com.sun.jersey.test.framework.AppDescriptor;
import com.sun.jersey.test.framework.JerseyTest;
import com.sun.jersey.test.framework.WebAppDescriptor;
import com.sun.jersey.test.framework.spi.container.grizzly2.web.GrizzlyWebTestContainerFactory;
import com.sun.jersey.test.framework.spi.container.inmemory.InMemoryTestContainerFactory;
import com.yammer.dropwizard.bundles.JavaBundle;
import com.yammer.dropwizard.jersey.JacksonMessageBodyProvider;
import com.yammer.dropwizard.jersey.LoggingExceptionMapper;
import com.yammer.dropwizard.jersey.caching.CacheControlledResourceMethodDispatchAdapter;
import com.yammer.dropwizard.json.Json;
import com.yammer.metrics.jersey.InstrumentedResourceMethodDispatchAdapter;

/**
 * A base test class for testing Dropwizard resources using the Grizzly web
 * server. Needed when we want Jersey to be able to inject an
 * {@link HttpServletRequest} object. The {@link InMemoryTestContainerFactory}
 * doesn't support this kind of injection.
 */
public abstract class GrizzlyResourceTest {
  private final Set<Object> singletons = Sets.newHashSet();
  private final Set<Class<?>> providers = Sets.newHashSet();
  private final List<Module> modules = Lists.newArrayList();

  private JerseyTest test;

  protected abstract void setUpResources() throws Exception;

  protected void addResource(Object resource) {
    singletons.add(resource);
  }

  public void addProvider(Class<?> klass) {
    providers.add(klass);
  }

  protected void addJacksonModule(Module module) {
    modules.add(module);
  }

  protected Json getJson() {
    return new Json();
  }

  protected Client client() {
    return test.client();
  }

  @Before
  public void setUpJersey() throws Exception {
    setUpResources();
    this.test = new JerseyTest(new GrizzlyWebTestContainerFactory()) {
      @Override
      protected AppDescriptor configure() {
        ClientConfig config = new DefaultClientConfig();

        // taken from DropwizardResourceConfig
        config.getFeatures().put(ResourceConfig.FEATURE_DISABLE_WADL, Boolean.TRUE);
        config.getSingletons().add(new LoggingExceptionMapper<Throwable>() { }); // create a subclass to pin it to Throwable
        config.getClasses().add(InstrumentedResourceMethodDispatchAdapter.class);
        config.getClasses().add(CacheControlledResourceMethodDispatchAdapter.class);

        for (Object provider : JavaBundle.DEFAULT_PROVIDERS) {
          config.getSingletons().add(provider);
        }
        for (Class<?> provider : providers) {
          config.getClasses().add(provider);
        }
        Json json = getJson();
        for (Module module : modules) {
          json.registerModule(module);
        }
        config.getSingletons().add(new JacksonMessageBodyProvider(json));
        config.getSingletons().addAll(singletons);

        return new WebAppDescriptor.Builder(<PACKEGE_NAME_WHERE_YOUR_RESOURCE_CLASSES_RESIDE>).clientConfig(config).build();
      }
    };
    test.setUp();
  }

  @After
  public void tearDownJersey() throws Exception {
    if (test != null) {
      test.tearDown();
    }
  }
}

pom.xml

<dependency>
  <groupId>com.sun.jersey.jersey-test-framework</groupId>
  <artifactId>jersey-test-framework-grizzly2</artifactId>
  <version>1.12</version>
</dependency>

SampleTest.java

ClientResponse response = client().resource("http://localhost:9998/oauth/register")
    .type(MediaType.APPLICATION_JSON)
    .post(ClientResponse.class, request);

Thanks. Helped a lot.