用poi从excel文档导入数据

 import org.apache.commons.lang3.StringUtils;
 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 import org.apache.poi.ss.usermodel.*;
 import org.apache.poi.xssf.usermodel.XSSFWorkbook;
 import org.springframework.web.multipart.MultipartFile;

 import java.io.IOException;
 import java.math.BigDecimal;
 import java.util.*;

 public class ImportExcelTool {
     public static List<Map<String, String>> readExcel(MultipartFile file) throws IOException {
         Workbook workbook = null;
         String fileName = file.getOriginalFilename();
         if (Objects.requireNonNull(fileName).endsWith(".xlsx"))
             workbook = new XSSFWorkbook(file.getInputStream());
         if (fileName.endsWith(".xls"))
             workbook = new HSSFWorkbook(file.getInputStream());
         Sheet sheet = Objects.requireNonNull(workbook).getSheetAt(0);
         int physicalNumberOfRows = sheet.getPhysicalNumberOfRows();

         Row row = sheet.getRow(1);
         List<String> fieldNames = new ArrayList<>();
         for (int i = 0; i < row.getLastCellNum(); i++)
             fieldNames.add(row.getCell(i).getRichStringCellValue().getString());

         List<Map<String, String>> lsMap = new ArrayList<>();

         for (int j = 3; j < physicalNumberOfRows; j++) {
             Map<String, String> dataMap = new HashMap<>();
             Row dataRow = sheet.getRow(j);
             if (dataRow == null)
                 break;
             for (int i = 0; i < dataRow.getLastCellNum(); i++) {
                 String val = getCellValue(dataRow.getCell(i));
                 dataMap.put(fieldNames.get(i), val);
             }
             if (dataMap.size() == 0)
                 break;

             lsMap.add(dataMap);
         }
         return lsMap;
     }

     private static String getCellValue(Cell cell) {
         if (cell == null)
             return "";
         if (cell.getCellType() == CellType.NUMERIC)
             if (DateUtil.isCellDateFormatted(cell))
                 return DateUtil.getJavaDate(cell.getNumericCellValue()).toString();
             else
                 return new BigDecimal(cell.getNumericCellValue()).toString();
         else if (cell.getCellType() == CellType.STRING)
             return StringUtils.trimToEmpty(cell.getStringCellValue());
         else if (cell.getCellType() == CellType.FORMULA)
             return StringUtils.trimToEmpty(cell.getCellFormula());
         else if (cell.getCellType() == CellType.BLANK)
             return "";
         else if (cell.getCellType() == CellType.BOOLEAN)
             return String.valueOf(cell.getBooleanCellValue());
         else if (cell.getCellType() == CellType.ERROR)
             return "ERROR";
         else
             return cell.toString().trim();

     }
 }