RestEasy Test example

CepCrawlerDAORestTest.java

public class CepCrawlerDAORestTest {

	@ClassRule
	public static final InMemoryRestServer server = new InMemoryRestServer(CepSearchProxy.class);

	@Path("/")
	public static class CepSearchProxy {

		@Path(CepCrawlerDAORest.CEP_SEARCH)
		@GET
		public Response buscaCep(){
			return Response.status(509).build();
		}

	}

	@Test
	public void crawByCep_successful() {
		Assert.assertEquals(509, server.target().path(CepCrawlerDAORest.CEP_SEARCH).request().get().getStatus());
	}
}

InMemoryRestServer.java

import io.undertow.Undertow;
import org.jboss.resteasy.client.jaxrs.ResteasyClientBuilder;
import org.jboss.resteasy.plugins.server.undertow.UndertowJaxrsServer;
import org.jboss.resteasy.spi.ResteasyDeployment;
import org.junit.rules.ExternalResource;

import javax.ws.rs.client.Client;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.Application;
import java.io.IOException;
import java.net.ServerSocket;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class InMemoryRestServer extends ExternalResource {

	public static final String HOST = "localhost";
	private static Map<String, String> contextParams = new HashMap<>();
	private static Map<String, String> initParams = new HashMap<>();
	private final Set<Class<?>> classes = new HashSet<>();

	private Application application = null;
	private int port;
	private UndertowJaxrsServer server;
	private final Client client = ResteasyClientBuilder.newClient();
	private WebTarget target;

	public InMemoryRestServer(Application application) {
		this.application = application;
	}
	public InMemoryRestServer(Class... objects) {
		for (Class clazz : objects) {
				classes.add(clazz);
		}
	}

	public static int findFreePort() throws IOException {
		ServerSocket server = new ServerSocket(0);
		int port = server.getLocalPort();
		server.close();
		return port;
	}

	@Override
	protected void before() throws Throwable {
		port = findFreePort();
		server = new UndertowJaxrsServer().start(Undertow.builder().addHttpListener(port, HOST));
		ResteasyDeployment deployment = new ResteasyDeployment();
		deployment.setDeploymentSensitiveFactoryEnabled(true);
		if(application == null){
			deployment.setApplication(new Application(){
				@Override
				public Set<Class<?>> getClasses() {
					return classes;
				}
			});
		}else{
			deployment.setApplication(application);
		}
		deployment.start();

		contextParams.put("contextKey1", "contextValue1");
		contextParams.put("contextKey2", "contextValue2");
		initParams.put("initKey1", "initValue1");
		initParams.put("initKey2", "initValue2");
		initParams.put("resteasy.servlet.context.deployment", "false");
		server.deploy(deployment, "/", contextParams, initParams);

		server.start();
		target = client.target(String.format("http://%s:%s", HOST, port));
	}

	@Override
	protected void after() {
		server.stop();
		client.close();
	}

	public Client getClient() {
		return client;
	}

	public WebTarget target(){
		return target;
	}
}