PowerMockito 在春季模拟静态测试控制器 3.2.4

Question

>我正在执行一些模拟测试，但是我对 1 个具有静态方法的类有一些问题，我在测试类的 setUp（） 方法中模拟了它

拥有这个类：

public class ResponseFileWriteHelper {

    public static void write(HttpServletResponse response, String fileName, StreamWriter writer) {
        response.setHeader("Cache-Control", "");
        response.setContentType("application/octet");
        if (!StringUtils.isBlank(fileName)) {
            response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
        }
        try {
            writer.doWrite(response.getOutputStream());
        }
        catch (Exception e) {
            throw new RuntimeException(e);
        }    
    }
}

这里我要测试的控制器：

public class ManageDeviceController extends SimpleFormController {

。

private void generateDevicexBeneficiaryList(
            Collection<Integer> selectedYears, PriorityAreaKey priorityAreaKey, Language language, Collection<DeviceStatus> statuses, HttpServletResponse response) throws Exception {
        final List<ReportItem> reportItems
            = DeviceListReportService.getDevicesxBeneficiaryForYears(selectedYears, priorityAreaKey, language, statuses);
        ResponseFileWriteHelper.write(response, "DevicesxBeneficiaryList.xls", new StreamWriter() {
            @Override
            public void doWrite(OutputStream outputStream) throws Exception {
                DeviceListExcelReportRendererBuilder.build().renderToStream(
                    reportItems, outputStream);
            }});
    }

}

这里是测试类

@RunWith(MockitoJUnitRunner.class)
public class SelectDeviceListExcelReportControllerTest {
    public void setUp() {
        PowerMockito.mockStatic (ResponseFileWriteHelper.class);
        EDeviceSessionContext.getInstance().setSession(httpSession);
        when(request.getSession()).thenReturn(httpSession);
        when(request.getLocale()).thenReturn(Locale.ENGLISH);
        messages.initialize();
    }
    @SuppressWarnings("unchecked")
    @Test
    @PrepareForTest(ResponseFileWriteHelper.class)
    public void successTest() throws Exception {
        TableItemBuilder tableItemBuilder = 
                new TableItemBuilder(new LabelCellItem("success.test"));
        List<ReportItem> expectedData = Arrays.asList(
            new ReportItem("success.test",Arrays.asList(tableItemBuilder.getTableItem())));
        final ByteArrayOutputStream resultData = new ByteArrayOutputStream();
        ServletOutputStream output = new ServletOutputStream() {
            @Override
            public void write(int val) throws IOException {
                resultData.write(val);
            }
        };
        when(response.getOutputStream()).thenReturn(output);
        when(deviceListReportService.getDevicesxBeneficiaryForYears(
            any(List.class), any(PriorityAreaKey.class), any(Language.class), any(Collection.class))).thenReturn(expectedData);

        doCall();
        //assertArrayEquals(expectedData, resultData);
    }
}

但是测试崩溃了，因为这里的java.lang.NullPointer

ResponseFileWriteHelper.write(response, "DevicesxBeneficiaryList.xls", new StreamWriter() {

Answer 1

@PrepareForTest()只在测试类中使用PowerMockRunner.class，因此您需要在测试类中添加@RunWith(PowerMockRunner.class)。

但是另一个问题是你真的想使用SpringJUnit4ClassRunner.class作为你的测试运行器，感谢powermock已经意识到这个问题，它提供了PowerMockRunnerDelegate注释来实现它。

工作副本将是这样的：

@WebAppConfiguration
@ContextConfiguration(locations = {
        "......"
        )
@RunWith(PowerMockRunner.class)
@PowerMockRunnerDelegate(SpringJUnit4ClassRunner.class)
@PowerMockIgnore("javax.management.*") // to specify that all classes under the specified package be loaded by the system class loader
@PrepareForTest({Static.class})
public void ControllerTest {
    public void testMockStatic() {
        PowerMockito.mockStatic(Static.class);
        ......
    }
}