[AssertionError，当我尝试编写单元测试时

Question

我正在创建处理器以收集数据并在列表中提供它们。但是，当我尝试为我的方法创建测试时，我正在捕获assertionerror。我在做什么错？

我的班级：

@AllArgsConstructor
public class ZteProcessor implements OurProcessor {

    private final static String VENDOR = "ZTE";

    private String jsonString;
    private Map<String, String> metricsGU;
    private Map<String, String> metricsUMTS;
    private Map<String, String> metricsLTE;

    @Override
    public List<TimingAdvance> getTA() throws ParseException, NotFoundPatternOrMetricsException {
        TimeAdvanceDataStore data = new TimeAdvanceDataStore();
        AllDataFromJSONFile fromJSONFile = ProcessorUtil.getAllData(jsonString);
        if (jsonString.contains("String")) {
            return data.allDataToTimingAdvance(VENDOR, fromJSONFile, metricsGU, 2);
        } else if (jsonString.contains("String-2")) {
            return data.allDataToTimingAdvance(VENDOR, fromJSONFile, metricsUMTS, 3);
        } else if (jsonString.contains("String3")) {
            return data.allDataToTimingAdvance(VENDOR, fromJSONFile, metricsLTE, 4);
        } else {
            throw new NotFoundPatternOrMetricsException();
        }
    }
}

我的测试：

@RunWith(PowerMockRunner.class)
@PrepareForTest({ProcessorUtil.class})
public class ZteProcessorTest {

    @Mock
    private AllDataFromJSONFile fromJSONFile;
    @Mock
    private TimeAdvanceDataStore data;

    private OurProcessor processor;

    private TimingAdvance timingAdvance = new TimingAdvance();

    private Map<String, String> metricsGU = new HashMap<>();
    private Map<String, String> metricsUMTS = new HashMap<>();
    private Map<String, String> metricsLTE = new HashMap<>();

    @Test
    public void getTATest() throws Exception {
        String jsonString = " { String : value}";
        processor = new ZteProcessor(jsonString, metricsGU, metricsUMTS, metricsLTE);
        List<TimingAdvance> list = new ArrayList<>();
        list.add(timingAdvance);
        PowerMockito.mockStatic(ProcessorUtil.class);

        when(ProcessorUtil.getAllData(jsonString)).thenReturn(fromJSONFile);
        when(data.allDataToTimingAdvance(jsonString, fromJSONFile, metricsGU, 2)).thenReturn(list);
        assertEquals(list, processor.getTA());
    }
}

Stacktrace：

java.lang.AssertionError: 
Expected :[TimingAdvance{filial='null', vendor='null', cellName='null', periodDate=null, taMetrics=null}]
Actual   :[]
<Click to see difference>


    at org.junit.Assert.fail(Assert.java:88)
    at org.junit.Assert.failNotEquals(Assert.java:834)
    at org.junit.Assert.assertEquals(Assert.java:118)
    at org.junit.Assert.assertEquals(Assert.java:144)

我的ZteProcessor使用类getAllData(jsonString)的静态方法ProcessorUtill。为此，我使用了powermock。

Answer 1

问题源于您对TimeAdvanceDataStore data模拟设置期望的事实，但是您正在测试的方法中创建TimeAdvanceDataStore的新实例。

由于您已经在使用PowerMockito，因此可以像这样创建新的对象

PowerMockito.whenNew(TimeAdvanceDataStore.class)
            .withAnyArguments().thenReturn(data);

最重要的是，考虑一下您的应用程序中有多少个ZTEProcessor和TimeAdvanceDataStores。您是否总是在每次调用getTA时都需要一个TimeAdvanceDataStore的新实例？

如果没有，只需在构造函数中传递TimeAdvanceDataStore。

如果是，当您不使用PowerMockito时，通常的方法是：

• 将TimeAdvanceDataStore的工厂传递给ZTEProcessor构造函数
• 将TimeAdvanceDataStore传递给getTA方法
• 提取构造TimeAdvanceDataStore的方法并在测试中覆盖它