java实现excel批量导入 数据到数据库中

poi 工具类：

public class PoiUtil {
/**
    * 导入xlsx格式的excel文件
    * @param in
    * @param entityClass
    * @param fieldMap
    * @param 
    * @return
     * @throws Exception
     */
   public static  List xlsxToList(InputStream in, Class entityClass,
                               Map fieldMap,Integer num) throws Exception {

      // 定义要返回的list
      List resultList = new ArrayList();

      org.apache.poi.ss.usermodel.Workbook wb = new XSSFWorkbook(in);

      int sheetSIze = wb.getNumberOfSheets();

      for (int j = 0; j< sheetSIze;j++) {

         if (j!=num){
            continue;
         }

         org.apache.poi.ss.usermodel.Sheet sheet = wb.getSheetAt(j);

         Row firstRow = sheet.getRow(2);

         int columnSize = firstRow.getLastCellNum();

         String[] excelFieldNames = new String[columnSize];

         // 获取Excel中的列名
         for (int i = 0; i < columnSize; i++) {
            if(firstRow.getCell(i) != null){
               firstRow.getCell(i).setCellType(XSSFCell.CELL_TYPE_STRING);
               excelFieldNames[i] = firstRow.getCell(i).getStringCellValue();
            }

         }

         // 判断需要的字段在Excel中是否都存在
         boolean isExist = true;
         String lackName = null;
         List excelFieldList = Arrays.asList(excelFieldNames);
         for (String cnName : fieldMap.values()) {
            if (!excelFieldList.contains(cnName)) {
               lackName = cnName;
               isExist = false;
               break;
            }
         }

         // 如果有列名不存在，则抛出异常，提示错误
         if (!isExist) {
//          throw new ServiceException("Excel中缺少必要的字段:" + lackName);
            throw new Exception("Excel中缺少必要的字段:" + lackName);
         }

         // 将列名和列号放入Map中,这样通过列名就可以拿到列号
         LinkedHashMap colMap = new LinkedHashMap();
         for (int i = 0; i < excelFieldNames.length; i++) {
            colMap.put(excelFieldNames[i], firstRow.getCell(i).getColumnIndex());
         }

         // 将sheet转换为list, rowNum从0开始， 总数 = lastNum + 1
         int rowCounts = sheet.getLastRowNum() + 1;

         for (int i = 3; i < rowCounts; i++) {
            // 新建要转换的对象
            T entity = entityClass.newInstance();

            Row row = sheet.getRow(i);

            //避免空行
            if(row == null){
               continue;
            }

            // 给对象中的字段赋值
            for (Entry entry : fieldMap.entrySet()) {
               // 获取英文字段名
               String enNormalName = entry.getKey();
               // 获取中文字段名
               String cnNormalName = entry.getValue();
               // 根据中文字段名获取列号
               int col = colMap.get(cnNormalName);
               String content = null;
               // 获取当前单元格中的内容
               if(row.getCell(col) != null){
                  row.getCell(col).setCellType(XSSFCell.CELL_TYPE_STRING);
                  content = row.getCell(col, Row.CREATE_NULL_AS_BLANK).getStringCellValue();
               }
               // 给对象赋值
               setFieldValueByName(enNormalName, content, entity);
            }

            resultList.add(entity);
         }
      }

      return resultList;
   }


   /**
    * @MethodName : getFieldByName
    * @Description : 根据字段名获取字段
    * @param fieldName
    *            字段名
    * @param clazz
    *            包含该字段的类
    * @return 字段
    */
   private static Field getFieldByName(String fieldName, Class clazz) {
      // 拿到本类的所有字段
      Field[] selfFields = clazz.getDeclaredFields();

      // 如果本类中存在该字段，则返回
      for (Field field : selfFields) {
         if (field.getName().equals(fieldName)) {
            return field;
         }
      }

      // 否则，查看父类中是否存在此字段，如果有则返回
      Class superClazz = clazz.getSuperclass();
      if (superClazz != null && superClazz != Object.class) {
         return getFieldByName(fieldName, superClazz);
      }

      // 如果本类和父类都没有，则返回空
      return null;
   }

   /**
    * @MethodName : setFieldValueByName
    * @Description : 根据字段名给对象的字段赋值
    * @param fieldName
    *            字段名
    * @param fieldValue
    *            字段值
    * @param o
    *            对象
    */
   private static void setFieldValueByName(String fieldName,
         Object fieldValue, Object o) throws Exception {

      if(fieldValue == null){
         return;
      }

      Field field = getFieldByName(fieldName, o.getClass());
      if (field != null) {
         field.setAccessible(true);
         // 获取字段类型
         Class fieldType = field.getType();

         //trim一下防止类型转换时报错
         String fieldValueStr = fieldValue.toString().trim();
         // 根据字段类型给字段赋值
         if (String.class == fieldType) {
            field.set(o, fieldValueStr);
         } else if ((Integer.TYPE == fieldType)
               || (Integer.class == fieldType)) {
            field.set(o, Integer.parseInt(fieldValueStr));
         } else if ((Long.TYPE == fieldType) || (Long.class == fieldType)) {
            field.set(o, Long.valueOf(fieldValueStr));
         } else if ((Float.TYPE == fieldType) || (Float.class == fieldType)) {
            field.set(o, Float.valueOf(fieldValueStr));
         } else if ((Short.TYPE == fieldType) || (Short.class == fieldType)) {
            field.set(o, Short.valueOf(fieldValueStr));
         } else if ((Double.TYPE == fieldType)
               || (Double.class == fieldType)) {
            field.set(o, Double.valueOf(fieldValueStr));
         } else if (Character.TYPE == fieldType) {
            if (fieldValue.toString().length() > 0) {
               field.set(o, fieldValue.toString().charAt(0));
            }
         } else if (Date.class == fieldType) {
            field.set(o, new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
                  .parse(fieldValueStr));
         } else {
            field.set(o, fieldValue);
         }
      } else {
         throw new Exception(o.getClass().getSimpleName() + "类不存在字段名 "
               + fieldName);
      }
   }
}

controller 层测试

@RestController
@Slf4j
@RequestMapping(value = "/excel")
public class ExcelTestContrller {

    /**
     * Description:上次excel 转对象
     */
    @RequestMapping(value = "/test")
    public void getClassify(@RequestParam(value = "file", required = false) MultipartFile file) {

        // key：封装的对象属性名 value：excel列名
        // sheet1
        Map fieldMap1 = new HashMap<>();
        fieldMap1.put("name1", "站址类型");
        fieldMap1.put("name2", "频点类别");
        fieldMap1.put("name3", "扇区配置");
        Map fieldMap2 = new HashMap<>();
        // sheet2
        fieldMap2.put("name1", "站址类型");
        fieldMap2.put("name2", "频点类别");
        fieldMap2.put("name3", "扇区配置");
        try {
            // 读第几个sheet num就传几
            List list1 = PoiUtil.xlsxToList(file.getInputStream(), Sheet1.class, fieldMap1,1);
            List list2 = PoiUtil.xlsxToList(file.getInputStream(), Sheet2.class, fieldMap2,2);
            List