Question

我有代码在哪里我使用随机访问文件来编写文件..为了测试该函数我试图验证writeBytes（）调用是否发生..但是，因为我在模拟随机访问文件..测试抛出和IO异常说＆＃39; Stream关闭＆＃39; ..我想这可能是因为我在嘲笑随机访问文件....任何建议/解决方法都表示赞赏。

@Test
    public void testWriteGradesIntoFile_WriteFirstRecord() throws Exception {
        final String firstRecord = new String(empID + "," + score);

        PowerMockito.whenNew(File.class).withArguments(outputFileName + ".csv")
                .thenReturn(outputFileMock);
        PowerMockito.whenNew(RandomAccessFile.class)
                .withArguments(outputFileMock, "rw").thenReturn(outputRAFMock);

        PowerMockito.mockStatic(WriteGradeReportToCSV.class);
        Mockito.when(WriteGradeReportToCSV.checkFileIsEmpty(outputRAFMock))
                .thenReturn(true);

        Mockito.when(outputRAFMock.length()).thenReturn(fileLength);
        Mockito.doNothing().when(outputRAFMock).seek(fileLength);

        Mockito.when(gradeReportMock.getEmpId()).thenReturn(empID);
        Mockito.when(gradeReportMock.getScore()).thenReturn(score);

        Mockito.doNothing().when(outputRAFMock).writeBytes(firstRecord);
        writeGradeToCSV.writeGradesIntoFile(gradeReportMock, outputFileName);

        Mockito.verify(outputRAFMock, Mockito.times(1)).close();
    }

它的功能如下：

File outputCSVFile = null;
        RandomAccessFile outputRAF = null;
        try {
            outputCSVFile = new File(outputFileName + ".csv");
            if (outputCSVFile != null) {
                outputRAF = new RandomAccessFile(outputCSVFile, "rw");
                if (checkFileIsEmpty(outputRAF)) {
                    // File is empty.Hence write the first record.
                    outputRAF.seek(outputRAF.length());
                    outputRAF.writeBytes(new StringBuffer(gradeReport
                            .getEmpId() + "," + gradeReport.getScore())
                            .toString());
                     outputRAF.close();
             }
      }

故障跟踪如下：

java.io.IOException: Stream Closed
    at java.io.RandomAccessFile.writeBytes0(Native Method)
    at java.io.RandomAccessFile.writeBytes(RandomAccessFile.java:520)
    at java.io.RandomAccessFile.writeBytes(RandomAccessFile.java:1123)
    at com.cerner.devcenter.wag.util.WriteGradeReportToCSV_writeGradesIntoFileTest.testWriteGradesIntoFile_WriteFirstRecord(WriteGradeReportToCSV_writeGradesIntoFileTest.java:132)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:68)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:310)
    at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:88)
    at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:96)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
    at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:86)
    at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
    at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:33)
    at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:118)
    at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:104)
    at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
    at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:53)
    at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:252)
    at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:141)
    at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:112)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:189)
    at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:165)
    at org.apache.maven.surefire.booter.ProviderFactory.invokeProvider(ProviderFactory.java:85)
    at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:115)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:75)

Answer 1

您可以使用JUnit的TemporaryFolder规则并使用真实文件而不是模拟。

Answer 2

在此代码中，您试图模拟最终方法，该方法不适用于Mockito。最终方法writeBytes()将在没有任何警告的情况下被调用。您可以使用PowerMock模拟最终方法，也可以重构原始代码以注入自己的RandomAccessFile测试实现。您几乎可以避免以这种方式测试第三方代码。

模拟随机访问文件

2 个答案: