我使用Java Servlets创建了一个Web系统，现在想要进行JUnit测试。我的dataManager只是将其提交到数据库的基本代码。你会如何使用JUnit测试Servlet？
我的代码示例允许用户注册/注册，这是通过AJAX从我的主页面提交的：
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException{
// Get parameters
String userName = request.getParameter("username");
String password = request.getParameter("password");
String name = request.getParameter("name");
try {
// Load the database driver
Class.forName("com.mysql.jdbc.Driver");
//pass reg details to datamanager
dataManager = new DataManager();
//store result as string
String result = dataManager.register(userName, password, name);
//set response to html + no cache
response.setContentType("text/html");
response.setHeader("Cache-Control", "no-cache");
//send response with register result
response.getWriter().write(result);
} catch(Exception e){
System.out.println("Exception is :" + e);
}
}
答案 0 :(得分：154)
您可以使用Mockito执行此操作，让模拟返回正确的参数，验证它们确实被调用（可选择指定次数），写入“结果”并验证它是否正确。
import static org.junit.Assert.*;
import static org.mockito.Mockito.*;
import java.io.*;
import javax.servlet.http.*;
import org.apache.commons.io.FileUtils;
import org.junit.Test;
public class TestMyServlet extends Mockito{
@Test
public void testServlet() throws Exception {
HttpServletRequest request = mock(HttpServletRequest.class);
HttpServletResponse response = mock(HttpServletResponse.class);
when(request.getParameter("username")).thenReturn("me");
when(request.getParameter("password")).thenReturn("secret");
StringWriter stringWriter = new StringWriter();
PrintWriter writer = new PrintWriter(stringWriter);
when(response.getWriter()).thenReturn(writer);
new MyServlet().doPost(request, response);
verify(request, atLeast(1)).getParameter("username"); // only if you want to verify username was called...
writer.flush(); // it may not have been flushed yet...
assertTrue(stringWriter.toString().contains("My expected string"));
}
}
答案 1 :(得分：44)
首先，在实际应用程序中，您永远不会在servlet中获取数据库连接信息;你可以在你的应用服务器中配置它。
但是，有些方法可以在没有容器运行的情况下测试Servlet。一种是使用模拟对象。 Spring为HttpServletRequest，HttpServletResponse，HttpServletSession等提供了一组非常有用的模拟：
使用这些模拟，你可以测试像
这样的东西如果请求中没有用户名，会发生什么？
如果请求中包含用户名，会发生什么？
等
然后您可以执行以下操作：
import static org.junit.Assert.assertEquals;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.junit.Before;
import org.junit.Test;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
public class MyServletTest {
private MyServlet servlet;
private MockHttpServletRequest request;
private MockHttpServletResponse response;
@Before
public void setUp() {
servlet = new MyServlet();
request = new MockHttpServletRequest();
response = new MockHttpServletResponse();
}
@Test
public void correctUsernameInRequest() throws ServletException, IOException {
request.addParameter("username", "scott");
request.addParameter("password", "tiger");
servlet.doPost(request, response);
assertEquals("text/html", response.getContentType());
// ... etc
}
}
答案 2 :(得分：3)
2018年2月更新：OpenBrace Limited has closed down，不再支持其ObMimic产品。
这是另一个替代方案，使用OpenBrace的ObMimic Servlet API测试双重库（披露：我是它的开发人员）。
package com.openbrace.experiments.examplecode.stackoverflow5434419;
import static org.junit.Assert.*;
import com.openbrace.experiments.examplecode.stackoverflow5434419.YourServlet;
import com.openbrace.obmimic.mimic.servlet.ServletConfigMimic;
import com.openbrace.obmimic.mimic.servlet.http.HttpServletRequestMimic;
import com.openbrace.obmimic.mimic.servlet.http.HttpServletResponseMimic;
import com.openbrace.obmimic.substate.servlet.RequestParameters;
import org.junit.Before;
import org.junit.Test;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* Example tests for {@link YourServlet#doPost(HttpServletRequest,
* HttpServletResponse)}.
*
* @author Mike Kaufman, OpenBrace Limited
*/
public class YourServletTest {
/** The servlet to be tested by this instance's test. */
private YourServlet servlet;
/** The "mimic" request to be used in this instance's test. */
private HttpServletRequestMimic request;
/** The "mimic" response to be used in this instance's test. */
private HttpServletResponseMimic response;
/**
* Create an initialized servlet and a request and response for this
* instance's test.
*
* @throws ServletException if the servlet's init method throws such an
* exception.
*/
@Before
public void setUp() throws ServletException {
/*
* Note that for the simple servlet and tests involved:
* - We don't need anything particular in the servlet's ServletConfig.
* - The ServletContext isn't relevant, so ObMimic can be left to use
* its default ServletContext for everything.
*/
servlet = new YourServlet();
servlet.init(new ServletConfigMimic());
request = new HttpServletRequestMimic();
response = new HttpServletResponseMimic();
}
/**
* Test the doPost method with example argument values.
*
* @throws ServletException if the servlet throws such an exception.
* @throws IOException if the servlet throws such an exception.
*/
@Test
public void testYourServletDoPostWithExampleArguments()
throws ServletException, IOException {
// Configure the request. In this case, all we need are the three
// request parameters.
RequestParameters parameters
= request.getMimicState().getRequestParameters();
parameters.set("username", "mike");
parameters.set("password", "xyz#zyx");
parameters.set("name", "Mike");
// Run the "doPost".
servlet.doPost(request, response);
// Check the response's Content-Type, Cache-Control header and
// body content.
assertEquals("text/html; charset=ISO-8859-1",
response.getMimicState().getContentType());
assertArrayEquals(new String[] { "no-cache" },
response.getMimicState().getHeaders().getValues("Cache-Control"));
assertEquals("...expected result from dataManager.register...",
response.getMimicState().getBodyContentAsString());
}
}
注意：
每个“模仿”对象的逻辑状态都有一个“mimicState”对象。这提供了Servlet API方法与模仿内部状态的配置和检查之间的明确区别。
您可能会对Content-Type的检查包含“charset = ISO-8859-1”感到惊讶。但是，对于给定的“doPost”代码，这是根据Servlet API Javadoc和HttpServletResponse自己的getContentType方法，以及在例如生成的实际Content-Type标头。 Glassfish 3.如果使用普通的模拟对象和您对API行为的期望，您可能没有意识到这一点。在这种情况下，它可能无关紧要，但在更复杂的情况下，这是一种意想不到的API行为，可能会对模拟造成一些嘲弄！
我使用response.getMimicState().getContentType()作为检查Content-Type的最简单方法并说明了上述观点，但如果您愿意，您确实可以自行检查“text / html”（使用{ {1}}）。检查Content-Type标头的方式与Cache-Control标头的方式相同。
对于此示例，将响应内容作为字符数据进行检查（使用Writer的编码）。我们还可以检查响应的Writer是否被使用而不是它的OutputStream（使用response.getMimicState().getContentTypeMimeType()），但我认为我们只关心结果输出，而不关心API调用产生它（虽然也可以检查......）。也可以将响应的主体内容检索为字节，检查Writer / OutputStream的详细状态等。
有关ObMimic的完整详情，可在OpenBrace网站免费下载。或者如果您有任何问题，可以与我联系（联系方式在网站上）。
答案 3 :(得分：2)
编辑：Cactus现在已经死了：http://attic.apache.org/projects/jakarta-cactus.html
你可能想看看仙人掌。
http://jakarta.apache.org/cactus/
项目说明
Cactus是一个简单的测试框架，用于测试服务器端Java代码（Servlet，EJB，Tag Libs，Filters，...）。
Cactus的目的是降低为服务器端代码编写测试的成本。它使用JUnit并对其进行扩展。
Cactus实现了一个容器内策略，这意味着测试是在容器内执行的。
答案 4 :(得分：2)
我发现Selenium测试在集成或功能（端到端）测试中更有用。我正在尝试使用 org.springframework.mock.web ，但我不是很远。我附加了一个带有 jMock 测试套件的样本控制器。
首先，控制器：
package com.company.admin.web;
import javax.validation.Valid;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.SessionAttributes;
import org.springframework.web.bind.support.SessionStatus;
import com.company.admin.domain.PaymentDetail;
import com.company.admin.service.PaymentSearchService;
import com.company.admin.service.UserRequestAuditTrail;
import com.company.admin.web.form.SearchCriteria;
/**
* Controls the interactions regarding to the refunds.
*
* @author slgelma
*
*/
@Controller
@SessionAttributes({"user", "authorization"})
public class SearchTransactionController {
public static final String SEARCH_TRANSACTION_PAGE = "searchtransaction";
private PaymentSearchService searchService;
//private Validator searchCriteriaValidator;
private UserRequestAuditTrail notifications;
@Autowired
public void setSearchService(PaymentSearchService searchService) {
this.searchService = searchService;
}
@Autowired
public void setNotifications(UserRequestAuditTrail notifications) {
this.notifications = notifications;
}
@RequestMapping(value="/" + SEARCH_TRANSACTION_PAGE)
public String setUpTransactionSearch(Model model) {
SearchCriteria searchCriteria = new SearchCriteria();
model.addAttribute("searchCriteria", searchCriteria);
notifications.transferTo(SEARCH_TRANSACTION_PAGE);
return SEARCH_TRANSACTION_PAGE;
}
@RequestMapping(value="/" + SEARCH_TRANSACTION_PAGE, method=RequestMethod.POST, params="cancel")
public String cancelSearch() {
notifications.redirectTo(HomeController.HOME_PAGE);
return "redirect:/" + HomeController.HOME_PAGE;
}
@RequestMapping(value="/" + SEARCH_TRANSACTION_PAGE, method=RequestMethod.POST, params="execute")
public String executeSearch(
@ModelAttribute("searchCriteria") @Valid SearchCriteria searchCriteria,
BindingResult result, Model model,
SessionStatus status) {
//searchCriteriaValidator.validate(criteria, result);
if (result.hasErrors()) {
notifications.transferTo(SEARCH_TRANSACTION_PAGE);
return SEARCH_TRANSACTION_PAGE;
} else {
PaymentDetail payment =
searchService.getAuthorizationFor(searchCriteria.geteWiseTransactionId());
if (payment == null) {
ObjectError error = new ObjectError(
"eWiseTransactionId", "Transaction not found");
result.addError(error);
model.addAttribute("searchCriteria", searchCriteria);
notifications.transferTo(SEARCH_TRANSACTION_PAGE);
return SEARCH_TRANSACTION_PAGE;
} else {
model.addAttribute("authorization", payment);
notifications.redirectTo(PaymentDetailController.PAYMENT_DETAIL_PAGE);
return "redirect:/" + PaymentDetailController.PAYMENT_DETAIL_PAGE;
}
}
}
}
接下来，测试：
package test.unit.com.company.admin.web;
import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.equalTo;
import static org.junit.Assert.assertThat;
import org.jmock.Expectations;
import org.jmock.Mockery;
import org.jmock.integration.junit4.JMock;
import org.jmock.integration.junit4.JUnit4Mockery;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.support.SessionStatus;
import com.company.admin.domain.PaymentDetail;
import com.company.admin.service.PaymentSearchService;
import com.company.admin.service.UserRequestAuditTrail;
import com.company.admin.web.HomeController;
import com.company.admin.web.PaymentDetailController;
import com.company.admin.web.SearchTransactionController;
import com.company.admin.web.form.SearchCriteria;
/**
* Tests the behavior of the SearchTransactionController.
* @author slgelma
*
*/
@RunWith(JMock.class)
public class SearchTransactionControllerTest {
private final Mockery context = new JUnit4Mockery();
private final SearchTransactionController controller = new SearchTransactionController();
private final PaymentSearchService searchService = context.mock(PaymentSearchService.class);
private final UserRequestAuditTrail notifications = context.mock(UserRequestAuditTrail.class);
private final Model model = context.mock(Model.class);
/**
* @throws java.lang.Exception
*/
@Before
public void setUp() throws Exception {
controller.setSearchService(searchService);
controller.setNotifications(notifications);
}
@Test
public void setUpTheSearchForm() {
final String target = SearchTransactionController.SEARCH_TRANSACTION_PAGE;
context.checking(new Expectations() {{
oneOf(model).addAttribute(
with(any(String.class)), with(any(Object.class)));
oneOf(notifications).transferTo(with(any(String.class)));
}});
String nextPage = controller.setUpTransactionSearch(model);
assertThat("Controller is not requesting the correct form",
target, equalTo(nextPage));
}
@Test
public void cancelSearchTest() {
final String target = HomeController.HOME_PAGE;
context.checking(new Expectations(){{
never(model).addAttribute(with(any(String.class)), with(any(Object.class)));
oneOf(notifications).redirectTo(with(any(String.class)));
}});
String nextPage = controller.cancelSearch();
assertThat("Controller is not requesting the correct form",
nextPage, containsString(target));
}
@Test
public void executeSearchWithNullTransaction() {
final String target = SearchTransactionController.SEARCH_TRANSACTION_PAGE;
final SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.seteWiseTransactionId(null);
final BindingResult result = context.mock(BindingResult.class);
final SessionStatus status = context.mock(SessionStatus.class);
context.checking(new Expectations() {{
allowing(result).hasErrors(); will(returnValue(true));
never(model).addAttribute(with(any(String.class)), with(any(Object.class)));
never(searchService).getAuthorizationFor(searchCriteria.geteWiseTransactionId());
oneOf(notifications).transferTo(with(any(String.class)));
}});
String nextPage = controller.executeSearch(searchCriteria, result, model, status);
assertThat("Controller is not requesting the correct form",
target, equalTo(nextPage));
}
@Test
public void executeSearchWithEmptyTransaction() {
final String target = SearchTransactionController.SEARCH_TRANSACTION_PAGE;
final SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.seteWiseTransactionId("");
final BindingResult result = context.mock(BindingResult.class);
final SessionStatus status = context.mock(SessionStatus.class);
context.checking(new Expectations() {{
allowing(result).hasErrors(); will(returnValue(true));
never(model).addAttribute(with(any(String.class)), with(any(Object.class)));
never(searchService).getAuthorizationFor(searchCriteria.geteWiseTransactionId());
oneOf(notifications).transferTo(with(any(String.class)));
}});
String nextPage = controller.executeSearch(searchCriteria, result, model, status);
assertThat("Controller is not requesting the correct form",
target, equalTo(nextPage));
}
@Test
public void executeSearchWithTransactionNotFound() {
final String target = SearchTransactionController.SEARCH_TRANSACTION_PAGE;
final String badTransactionId = "badboy";
final PaymentDetail transactionNotFound = null;
final SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.seteWiseTransactionId(badTransactionId);
final BindingResult result = context.mock(BindingResult.class);
final SessionStatus status = context.mock(SessionStatus.class);
context.checking(new Expectations() {{
allowing(result).hasErrors(); will(returnValue(false));
atLeast(1).of(model).addAttribute(with(any(String.class)), with(any(Object.class)));
oneOf(searchService).getAuthorizationFor(with(any(String.class)));
will(returnValue(transactionNotFound));
oneOf(result).addError(with(any(ObjectError.class)));
oneOf(notifications).transferTo(with(any(String.class)));
}});
String nextPage = controller.executeSearch(searchCriteria, result, model, status);
assertThat("Controller is not requesting the correct form",
target, equalTo(nextPage));
}
@Test
public void executeSearchWithTransactionFound() {
final String target = PaymentDetailController.PAYMENT_DETAIL_PAGE;
final String goodTransactionId = "100000010";
final PaymentDetail transactionFound = context.mock(PaymentDetail.class);
final SearchCriteria searchCriteria = new SearchCriteria();
searchCriteria.seteWiseTransactionId(goodTransactionId);
final BindingResult result = context.mock(BindingResult.class);
final SessionStatus status = context.mock(SessionStatus.class);
context.checking(new Expectations() {{
allowing(result).hasErrors(); will(returnValue(false));
atLeast(1).of(model).addAttribute(with(any(String.class)), with(any(Object.class)));
oneOf(searchService).getAuthorizationFor(with(any(String.class)));
will(returnValue(transactionFound));
oneOf(notifications).redirectTo(with(any(String.class)));
}});
String nextPage = controller.executeSearch(searchCriteria, result, model, status);
assertThat("Controller is not requesting the correct form",
nextPage, containsString(target));
}
}
我希望这可能有所帮助。
答案 5 :(得分：1)
使用Selenium进行基于Web的单元测试。有一个名为Selenium IDE的Firefox插件可以记录网页上的操作并导出到使用Selenium RC来运行测试服务器的JUnit测试用例。
答案 6 :(得分：1)
public class WishServletTest {
WishServlet wishServlet;
HttpServletRequest mockhttpServletRequest;
HttpServletResponse mockhttpServletResponse;
@Before
public void setUp(){
wishServlet=new WishServlet();
mockhttpServletRequest=createNiceMock(HttpServletRequest.class);
mockhttpServletResponse=createNiceMock(HttpServletResponse.class);
}
@Test
public void testService()throws Exception{
File file= new File("Sample.txt");
File.createTempFile("ashok","txt");
expect(mockhttpServletRequest.getParameter("username")).andReturn("ashok");
expect(mockhttpServletResponse.getWriter()).andReturn(new PrintWriter(file));
replay(mockhttpServletRequest);
replay(mockhttpServletResponse);
wishServlet.doGet(mockhttpServletRequest, mockhttpServletResponse);
FileReader fileReader=new FileReader(file);
int count = 0;
String str = "";
while ( (count=fileReader.read())!=-1){
str=str+(char)count;
}
Assert.assertTrue(str.trim().equals("Helloashok"));
verify(mockhttpServletRequest);
verify(mockhttpServletResponse);
}
}
答案 7 :(得分：1)
另一种方法是创建一个嵌入式服务器来托管主机＆＃34;您的servlet，允许您使用库来编写调用，以便调用实际的服务器（这种方法的用处在一定程度上取决于您可以轻松地进行＃34;对服务器进行合法的编程调用 - 我正在测试一个JMS（Java Messaging Service）访问点，客户端很多。
你可以去几条不同的路线 - 通常的两条路线是tomcat和码头。
警告：选择要嵌入的服务器时要注意的是您正在使用的servlet-api的版本（提供类似HttpServletRequest的类的库）。如果你使用2.5，我发现Jetty 6.x运行良好（这是我在下面给出的例子）。如果您正在使用servlet-api 3.0，那么嵌入式tomcat-7似乎是一个不错的选择，但是我不得不放弃尝试使用它，因为我测试的应用程序使用的是servlet-api 2.5。在尝试配置或启动服务器时，尝试将两者混合将导致NoSuchMethod和其他此类异常。
您可以设置这样的服务器（Jetty 6.1.26，servlet-api 2.5）：
public void startServer(int port, Servlet yourServletInstance){
Server server = new Server(port);
Context root = new Context(server, "/", Context.SESSIONS);
root.addServlet(new ServletHolder(yourServletInstance), "/servlet/context/path");
//If you need the servlet context for anything, such as spring wiring, you coudl get it like this
//ServletContext servletContext = root.getServletContext();
server.start();
}
答案 8 :(得分：0)