<dependency>
  <groupId>org.apache.poi</groupId>
  <artifactId>poi</artifactId>
  <version>RELEASE</version>
</dependency>
<dependency>
  <groupId>org.apache.poi</groupId>
  <artifactId>poi-ooxml</artifactId>
  <version>RELEASE</version>
</dependency>

Workbook workbook = null;
try {
  if (file.getPath().endsWith("xls")) {
    System.out.println("這是2003版本");
    workbook = new XSSFWorkbook(new FileInputStream(file));
  } else if (file.getPath().endsWith("xlsx")){
    workbook = new HSSFWorkbook(new FileInputStream(file));
    System.out.println("這是2007版本");
  }
      
} catch (IOException e) {
  e.printStackTrace();
}

// 獲取第一個張表
Sheet sheet = workbook.getSheetAt(0);
   
// 獲取每行中的字段
for (int i = 0; i <= sheet.getLastRowNum(); i++) {
  Row row = sheet.getRow(i);  // 獲取行

  // 獲取單元格中的值
  String studentNum = row.getCell(0).getStringCellValue();  
  String name = row.getCell(1).getStringCellValue();
  String phone = row.getCell(2).getStringCellValue();
}

List<Student> studentList = new ArrayList<>();

for (int i = 0; i <= sheet.getLastRowNum(); i++) {
  Row row = sheet.getRow(i);  // 獲取行

  // 獲取單元格中的值
  String studentNum = row.getCell(0).getStringCellValue();  
  String name = row.getCell(1).getStringCellValue();
  String phone = row.getCell(2).getStringCellValue();
  
  Student student = new Student();
  student.setStudentNumber(studentNum);
  student.setName(name);
  student.setPhoneNumber(phone);
  
  studentList.add(student);
}

// 持久化
studentRepository.saveAll(studentList);