ApachePOI-给予NoClasseDelferor

Question

    public static void main(String [] args){
        String excelFilePath = "D:\\JavaBooks.xls";

        try {
            FileInputStream inputStream = new FileInputStream(new File(excelFilePath));
            Workbook workbook = WorkbookFactory.create(inputStream);

            Sheet sheet = workbook.getSheetAt(0);

            Object[][] bookData = {
                    {"The Passionate Programmer", "Chad Fowler", 16},
                    {"Software Craftmanship", "Pete McBreen", 26},
                    {"The Art of Agile Development", "James Shore", 32},
                    {"Continuous Delivery", "Jez Humble", 41},
            };

            int rowCount = sheet.getLastRowNum();

            for (Object[] aBook : bookData) {
                Row row = sheet.createRow(++rowCount);

                int columnCount = 0;

                Cell cell = row.createCell(columnCount);
                cell.setCellValue(rowCount);

                for (Object field : aBook) {
                    cell = row.createCell(++columnCount);
                    if (field instanceof String) {
                        cell.setCellValue((String) field);
                    } else if (field instanceof Integer) {
                        cell.setCellValue((Integer) field);
                    }
                }

            }

            inputStream.close();

            FileOutputStream outputStream = new FileOutputStream("D:\\JavaBooks.xls");
            workbook.write(outputStream);
            workbook.close();
            outputStream.close();

        } catch (IOException | EncryptedDocumentException
                ex) {
            ex.printStackTrace();
        }
    }

}

在执行此代码时，它在线程"main"java.lang.NoClassDefFoundError： org/apache/Commons/math3/util/ArithmeticUtils在org.apache.poi.poifs.property.RootProperty.set大小（RootProperty.java:59）在org.apache.poi.poifs.property.DirectoryProperties.（DirectoryProperty.java:52）在org.apache.poi.poifs.property.RootProperties.（RootProperty.java:31）在org.apache.poi.poifs.filesystem.POIFSFileSystem.（POIFSFileSystem.java:102）在org.apache.poi.poifs.filesystem.POIFSFileSystem.（POIFSFileSystem.java:274）在org.apache.poi.ss.usermodel.WorkbookFactory.create（WorkbookFactory.java:252）在org.apache.poi.ss.usermodel.WorkbookFactory.create（WorkbookFactory.java:221）在NewClass. main（NewClass. java： 31）引起的：java. lang. ClassNotFound异常：org. apache.公共品. math3. util. ArithmeticUtils在java. net. URLClassLoader. findClass（URLClassLoader. java： 381）在java. lang. ClassLoader. loadClass（ClassLoader. java： 424）在sun. misc. Launcher$AppClassLoader. loadClass（Launcher. java： 335）在java. lang. ClassLoader. loadClass（ClassLoader. java： 357）...9更多

Answer 1

将Apache公有数学添加到您的依赖项。

例如在Maven中：

<dependency>
  <groupId>org.apache.commons</groupId>
  <artifactId>commons-math3</artifactId>
  <version>3.6.1</version>
</dependency>

更多选择：https://mvnrepository.com/artifact/org.apache.commons/commons-math3/3.6.1

关于ClassNotFoundErrors的更多信息可以在这里找到：为什么在Java中会出现NoClassDefFoundError？