java - 尽管文件存在，Mockito 返回 FileNotFoundException

Question

我正在尝试对新创建的 Spring Boot 服务类运行测试。 StringWriter 内容是常规 XML，带有几行名为“transaction”的标签。

PrepareExcelServiceTest.class

@SpringBootTest
@RunWith(MockitoJUnitRunner.class)
public class PrepareExcelServiceTest {

    @Rule
    public MockitoRule mockitoRule = MockitoJUnit.rule();

    private static final Logger log = LoggerFactory.getLogger(PrepareExcelService.class);

    @Test
    public void testPrepareExcelService() throws ParserConfigurationException, SAXException, IOException {
        PrepareExcelService prepareExcelService = new PrepareExcelService();
        StringWriter xmlStringWriter = new StringWriter();

        Source source = new StreamSource("./view/xml/0_dummy.xml");
        xmlStringWriter.write(source.toString());

        prepareExcelService.prepareDocument(xmlStringWriter);
    }
}

PrepareExcelService.class

@Service
public class PrepareExcelService {

    private HSSFWorkbook workbook;
    private HSSFSheet spreadsheet;

    public void prepareDocument(StringWriter xmlStringWriter) throws IOException,
                                                                            SAXException, ParserConfigurationException {
        workbook = setupWorkBook();
        spreadsheet = setupSheet(workbook);

        Document document = parseXMLStringWriter(xmlStringWriter);
        fillContent(document, spreadsheet);

        FileOutputStream output = new FileOutputStream(new File("TestExcelFile.xls"));
        workbook.write(output);
        output.flush();
        output.close();
    }

    private HSSFWorkbook setupWorkBook() {
        HSSFWorkbook workbook = new HSSFWorkbook();
        HSSFCellStyle cellStyle = workbook.createCellStyle();

        cellStyle.setBorderLeft(BorderStyle.MEDIUM);
        cellStyle.setBorderRight(BorderStyle.MEDIUM);
        cellStyle.setBorderTop(BorderStyle.MEDIUM);
        cellStyle.setBorderBottom(BorderStyle.MEDIUM);
        cellStyle.setIndention((short)4);
        cellStyle.setWrapText(true);

        HSSFFont font = workbook.createFont();
        font.setFontHeightInPoints((short)24);
        font.setFontName("Courier New");
        font.setItalic(false);
        cellStyle.setFont(font);

        return workbook;
    }

    private HSSFSheet setupSheet(HSSFWorkbook workbook) {
        HSSFSheet spreadSheet = workbook.createSheet("spreadSheet");
        return spreadSheet;
    }

    private Document parseXMLStringWriter(StringWriter xmlStringWriter) throws ParserConfigurationException,
                                                                                            IOException, SAXException {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();

        return builder.parse(xmlStringWriter.toString());
    }

    private void fillContent (Document document, HSSFSheet spreadSheet) {
        HSSFRow row = spreadSheet.createRow(0);
        HSSFCell cell = row.createCell((short) 1);

        NodeList nodeList = document.getElementsByTagName("transaction");
        HSSFRow rowOne = spreadSheet.createRow(1);

        cell.setCellValue("Spreadsheet Header Row");

        for (int i = 0; i < nodeList.getLength(); i++) {
            switch (i) {
                case 0:
                    cell = rowOne.createCell((short) 0);
                    cell.setCellValue("transaction");
                    cell = rowOne.createCell((short) 1);
                    cell.setCellValue(((Element) (nodeList.item(0))).getElementsByTagName("transaction").item(0)
                                                                                        .getFirstChild().getNodeValue());
                    break;
                default:
                    break;
            }
        }
    }
}

在测试此服务时，尽管文件存在并且其他服务通过 StringWriter 与它正确交互，但我收到以下异常。

java.io.FileNotFoundException: ...\javax.xml.transform.stream.StreamSource@4439f31e (The system cannot find the file specified)

    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(FileInputStream.java:195)
    at java.io.FileInputStream.<init>(FileInputStream.java:138)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)
    at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:90)
    at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:188)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(XMLEntityManager.java:623)
    at com.sun.org.apache.xerces.internal.impl.XMLVersionDetector.determineDocVersion(XMLVersionDetector.java:189)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:812)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:777)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
    at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:243)
    at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:339)
    at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:177)
    at ee.estcard.repgen.service.PrepareExcelService.parseXMLStringWriter(PrepareExcelService.java:78)
    at ee.estcard.repgen.service.PrepareExcelService.prepareDocument(PrepareExcelService.java:39)
    at ee.estcard.repgen.service.PrepareExcelServiceTest.testPrepareExcelService(PrepareExcelServiceTest.java:48)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.mockito.internal.junit.JUnitRule$1.evaluate(JUnitRule.java:16)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnit45AndHigherRunnerImpl.java:37)
    at org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:117)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:42)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:262)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:84)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)

我认为问题在于我对 StringWriter 的错误使用，但由于我对 Java 的菜鸟知识，我仍然无法解决这个问题。

Answer 1

不，您的问题与您如何使用StreamSource有关，确实调用source.toString()不会为您提供您所期望的源内容，而是类似 javax.xml.transform.stream.StreamSource@4439f31e 的内容正如您在堆栈跟踪中看到的那样。

只需删除您的 StringWriter并使用 InputSource在您的代码中修复您的代码，同时也使其更加灵活，因为使用 InputSource是对许多不同类型的源开放的大门，此外，加载文件的内容不是一个好的做法，应该避免，因为如果文件太大，如果无法放入堆中，您可能会面临 OOME。

在 PrepareExcelServiceTest

PrepareExcelService prepareExcelService = new PrepareExcelService();
InputSource source = new InputSource("./view/xml/0_dummy.xml");
prepareExcelService.prepareDocument(source);

在方法parseXMLStringWriter中更名

private Document parseXML(InputSource source) throws ParserConfigurationException,
    IOException, SAXException {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    DocumentBuilder builder = factory.newDocumentBuilder();

    return builder.parse(source);
}

在方法prepareDocument中

public void prepareDocument(InputSource source) throws IOException,
    SAXException, ParserConfigurationException {
    ...

    Document document = parseXML(source);

    ...
}