HelloServlet.java

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloServlet extends HttpServlet {

	@Override
	public void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		PrintWriter out = resp.getWriter();
		out.println("<h1>Hello, World!</h1>");
		out.flush();
	}

}

HelloServletTest.java

import static org.junit.Assert.*;

import java.util.Vector;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.mortbay.jetty.testing.HttpTester;
import org.mortbay.jetty.testing.ServletTester;

public class HelloServletTest {

	private ServletTester tester;

	@Before
	public void setUp() throws Exception {
		tester = new ServletTester();
		tester.setContextPath("/context");
		tester.addServlet(HelloServlet.class, "/hello/*");
		tester.start();
	}

	@After
	public void tearDown() throws Exception {
		tester.stop();
	}

	@Test
	public void testDefaultServlet() throws Exception {
		HttpTester request = withRequest("/context/hello/info", null);

		HttpTester response = new HttpTester();
		response.parse(tester.getResponses(request.generate()));

		assertNull(response.getMethod());
		assertEquals(200, response.getStatus());
		assertEquals("<h1>Hello, World!</h1>", response.getContent().trim());
	}

	private HttpTester withRequest(String path, Vector<String[]> parameters) {
		String requestParameters = "";
		for (String[] params : parameters) {
			requestParameters += ("".equals(requestParameters) ? "?" : "&");
			requestParameters += params[0] + "=" + params[1];
		}
		String uri = path;
		if (requestParameters != "")
			uri += requestParameters;
		HttpTester request = new HttpTester();
		request.setMethod("GET");
		request.setHeader("Host", "127.0.0.1");
		request.setURI(uri);
		request.setVersion("HTTP/1.0");
		return request;
	}

}