excel批量导入，从第二行拿取字段类型

servimport org.apache.dolphinscheduler.api.service.BaseService;

import org.apache.dolphinscheduler.api.service.FileService;
import org.apache.dolphinscheduler.common.enums.Status;
import org.apache.dolphinscheduler.common.model.Result;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.ss.usermodel.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.io.InputStream;
import java.text.SimpleDateFormat;
import java.util.*;


@Service
public class ScanExcelService{

    private static final Logger logger = LoggerFactory.getLogger(FileService.class);

    private static final String OFFICE_EXCEL_XLS = ".xls";

    private static final String OFFICE_EXCEL_XLSX = ".xlsx";


    private static final String EXCEL_NAME = "excelName";

    private static final String EXCEL_TYPE = "excelType";

    private static String ERRORVALUETYPE = "非法字符";

    private static String UNKNOWVALUETYPE = "未知类型";

    public List<Map<String,String>> scanValue(MultipartFile file) throws Exception {

        //检验excel文件
        checkFile(file);

        //读取字段
        Workbook workbook = null;
        try {
            InputStream input = file.getInputStream();
            workbook = WorkbookFactory.create(input);
        } catch (Exception e) {
            logger.error("io.lrd.datax.utils.ExcelReaderUtil analysis error", e);
            throw new Exception("Error parsing Excel format");
        }
        Sheet sheet = workbook.getSheetAt(0);

        if (sheet == null) {
            throw new Exception("Error parsing Excel format");
        }

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

        //遍历行
        for (int rownum = 0; rownum < sheet.getLastRowNum(); rownum++) {
            //拿到行
            Row row = sheet.getRow(rownum);
            if (row == null){
                throw new Exception("current row data cannot be empty");
            }

            //遍历列
            for (int cellnum = 0; cellnum < row.getLastCellNum(); cellnum++) {
                Map<String, String> excelMap = new HashMap<>();
                if (rownum == 0) {
                    //拿到单元格数据内容
                    String cellValue = getCellValue(row.getCell(cellnum));
                    excelMap.put(EXCEL_NAME, cellValue);
                    excelMap.put(EXCEL_TYPE, "");
                    list.add(excelMap);
                }
                if (rownum == 1) {
                    Map<String, String> currentExcelMap = list.get(cellnum);
                    String cellType = getCellType(row.getCell(cellnum));
                    currentExcelMap.put(EXCEL_TYPE, cellType);
                }

            }

        }return list;

    }

    /**
     * 得到类型
     *
     * @param cell
     * @return
     */
    private String getCellType(Cell cell) {
        String type = "";
        if (cell == null) {
            return null;
        } else if (cell.getCellTypeEnum().equals(CellType.NUMERIC)) {
            if (HSSFDateUtil.isCellDateFormatted(cell)) {
                type = "Date";
            } else {
                type = "int";
            }
        } else if (cell.getCellTypeEnum().equals(CellType.STRING)) {
            type = "String";
        } else if (cell.getCellTypeEnum().equals(CellType.BOOLEAN)) {
            type = "Boolean";
        } else if (cell.getCellTypeEnum().equals(CellType.FORMULA)) {
            type = "String";
        } else if (cell.getCellTypeEnum().equals(CellType.BLANK)) {
            type = "String";
        }
        return type.trim();
    }


    /**
     * 得到数据
     *
     * @param cell
     * @return
     */
    private String getCellValue(Cell cell) {

        String value = "";
        if (cell != null) {
            CellType cellType = cell.getCellTypeEnum();
            if (cellType.equals(CellType.NUMERIC)) {
                if (HSSFDateUtil.isCellDateFormatted(cell)) {// 处理日期格式、时间格式
                    SimpleDateFormat sdf = null;
                    Date d = cell.getDateCellValue();
                    sdf = new SimpleDateFormat("yyyy/MM/dd");
                    value = sdf.format(d);
                    // 验证short值
                } else if (cell.getCellStyle().getDataFormat() == 0) {//处理数值格式
                    cell.setCellType(CellType.STRING);
                    value = String.valueOf(cell.getRichStringCellValue().getString());
                } else {
                    value = String.valueOf(cell.getNumericCellValue());
                }
            } else if (cellType.equals(CellType.STRING)) {
                value = cell.getStringCellValue();
            } else if (cellType.equals(CellType.BOOLEAN)) {
                value = cell.getBooleanCellValue() + "";
            } else if (cellType.equals(CellType.FORMULA)) {
                value = cell.getCellFormula() + "";
            } else if (cellType.equals(CellType.BLANK)) {
                value = "";
            } else if (cellType.equals(CellType.ERROR)) {
                value = ERRORVALUETYPE;
            } else {
                value = UNKNOWVALUETYPE;
            }
        }

        return value.trim();
    }


    /**
     * 检验excel文件
     *
     * @param file
     * @throws Exception
     */
    private static void checkFile(MultipartFile file) throws Exception {
        if (file == null || file.isEmpty()) {
            throw new Exception("Error file cannot be empty");
        }
        if (!file.getOriginalFilename().endsWith(OFFICE_EXCEL_XLS)
                && !file.getOriginalFilename().endsWith(OFFICE_EXCEL_XLSX)) {
            throw new Exception("Error parsing Excel format");
        }
    }
}