实现doFilter() 如何正确地覆盖过滤器使用JUnit？
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
throws java.io.IOException, javax.servlet.ServletException
{
HttpServletRequest request = (HttpServletRequest) servletRequest;
HttpServletResponse response = (HttpServletResponse) servletResponse;
String currentURL = request.getRequestURI();
if (!currentURL.equals("/maintenance.jsp") && modeService.getOnline())
{
response.sendRedirect("/maintenance.jsp");
}
filterChain.doFilter(servletRequest, servletResponse);
}
ServletRequest ， ServletResponse和FilterChain的所有接口，让您可以轻松地为他们创造测试桩，手工或用讽刺的框架。
让模拟对象可配置的，这样就可以准备罐头回应getRequestURI()等，你可以查询ServletResponse的断言的sendRedirect已被调用。
注入模拟ModeService。
调用的doFilter通过模拟的ServletRequest，ServletResponse的和FilterChain作为它的参数。
@Test
public void testSomethingAboutDoFilter() {
MyFilter filterUnderTest = new MyFilter();
filterUnderTest.setModeService(new MockModeService(ModeService.ONLINE));
MockFilterChain mockChain = new MockFilterChain();
MockServletRequest req = new MockServletRequest("/maintenance.jsp");
MockServletResponse rsp = new MockServletResponse();
filterUnderTest.doFilter(req, rsp, mockChain);
assertEquals("/maintenance.jsp",rsp.getLastRedirect());
}
在实践中你要设置进入一个@Before setUp()方法，多写@Test方法来涵盖所有可能的执行路径。
......你可能会使用像JMock的或一个的Mockito嘲讽的框架来创建嘲弄，而不是假想MockModeService等我在这里使用。
这是一个单元测试的方法，而不是一个集成测试。 你只行使被测单元（和测试代码）。
你可以使用一个嘲讽的框架，以嘲笑以上HttpServletRequest ， HttpServletResponse和FilterChain对象及其行为。 根据不同的框架，你才能在哪里拍摄的嘲笑对象的代码正确动作的执行过程中，以验证是否具有某些功能。
对于使用模拟的Mockito框架时例如，所提供doFilter()方法可以是使用的JUnit下面测试用例测试：
@Test
public void testDoFilter() throws IOException, ServletException {
// create the objects to be mocked
HttpServletRequest httpServletRequest = mock(HttpServletRequest.class);
HttpServletResponse httpServletResponse = mock(HttpServletResponse.class);
FilterChain filterChain = mock(FilterChain.class);
// mock the getRequestURI() response
when(httpServletRequest.getRequestURI()).thenReturn("/otherurl.jsp");
MaintenanceFilter maintenanceFilter = new MaintenanceFilter();
maintenanceFilter.doFilter(httpServletRequest, httpServletResponse,
filterChain);
// verify if a sendRedirect() was performed with the expected value
verify(httpServletResponse).sendRedirect("/maintenance.jsp");
}
如果您在使用Spring那么它有自己的嘲笑：
- org.springframework.mock.web.MockFilterChain
- org.springframework.mock.web.MockHttpServletRequest
- org.springframework.mock.web.MockHttpServletResponse
例如，您可以添加标题，并设置测试URI。
所以，你的测试可以是水木清华这样的：
@RunWith(MockitoJUnitRunner.class)
public class TokenAuthenticationFilterTest {
private static final String token = "260bce87-6be9-4897-add7-b3b675952538";
private static final String testUri = "/testUri";
@Mock
private SecurityService securityService;
@InjectMocks
private TokenAuthenticationFilter tokenAuthenticationFilter = new TokenAuthenticationFilter();
@Test
public void testDoFilterInternalPositiveScenarioWhenTokenIsInHeader() throws ServletException, IOException {
MockHttpServletRequest request = new MockHttpServletRequest();
request.addHeader(TOKEN, token);
request.setRequestURI(testUri);
MockHttpServletResponse response = new MockHttpServletResponse();
MockFilterChain filterChain = new MockFilterChain();
when(securityService.doesExistToken(token)).thenReturn(true);
tokenAuthenticationFilter.doFilterInternal(request, response, filterChain);
assertThat(response.getStatus()).isEqualTo(HttpStatus.OK.value());
}
}
