POI导入

String fileName = file.getOriginalFilename();
Workbook workbook = null;
ExcelUtil eu = new ExcelUtil();
//判断文件类型
if (fileName.endsWith("xls")) {
    try {
        log.info("这是一个后缀是xls版本的，调用HSSFWorkbook老版本");
        workbook = new HSSFWorkbook(file.getInputStream());// 2003版本
    } catch (IOException e) {
        e.printStackTrace();
    }
} else if (fileName.endsWith("xlsx")) {
    try {
        log.info("这是一个后缀是xlsx版本的，调用XSSFWorkbook老版本");
        workbook = new XSSFWorkbook(file.getInputStream());// 2007版本
    } catch (IOException e) {
        e.printStackTrace();
    }
//不是excel文件就提示错误
} else {
    try {
        return  JsonResult.parameterError("文件不是Excel文件");
    } catch (Exception e) {
        e.printStackTrace();
    }
}

//获取到当前sheet页数据
Sheet sheet = workbook.getSheet("工作表");
int rows = sheet.getLastRowNum();
if (rows == 0) {
    try {
        return JsonResult.parameterError("数据为空请重新填写数据");
    } catch (Exception e) {
        e.printStackTrace();
    }
}

//获取Excel文档中的第一个表单
Sheet sht0 = workbook.getSheetAt(0);
Row ro = sht0.getRow(1);
boolean flag = false;
Cell cell = ro.getCell(4);
String cellName = null;
if (cell != null) {
    cellName = cell.getStringCellValue();
}
if (cellName != null && cellName.trim().length() > 0) {
    if (!"*性别".equals(cellName)) {
        throw new Exception("文件不是Excel文件");;
    }
} else {
    cell = ro.getCell(2);
    if (cell != null) {
        cellName = cell.getStringCellValue();
    }
    if (cellName == null || (cellName.trim().length() > 0 && !"*性别".equals(cellName))) {
       throw new Exception("文件不是Excel文件");;
    }
}

//对Sheet中的每一行进行迭代
int count=0;
for (Row r : sht0) {
    //如果当前行的行号（从0开始）未达到2（第三行）则从新循环
    int rnum = r.getRowNum() + 1;
    if (r.getRowNum() < 2) {
        continue;
    }
    eu.getCellValue(r.getCell(0));
    count++;
}
System.out.println("---:"+count);


/**
 * 获取Excel单元格的值
 *
 * @param cell
 * @return
 */
public String getCellValue(Cell cell) {
    String value = "";
    if (cell != null) {
        switch (cell.getCellTypeEnum()) {
            case NUMERIC:  //数字
                value = cell.getNumericCellValue() + "";
                if (HSSFDateUtil.isCellDateFormatted(cell)) {
                    Date date = cell.getDateCellValue();
                    if (date != null) {
                        value = new SimpleDateFormat("yyyy-MM-dd").format(date);//日期格式化
                    } else {
                        value = "";
                    }
                } else {
                    //在解析cell的时候，数字类型默认是double的，但是想要的的整数的类型，需要格式化，很重要
                    value = new DecimalFormat("0").format(cell.getNumericCellValue());
                }
                break;
            case STRING://字符串
                value = cell.getStringCellValue();
                break;
            case BOOLEAN://boolean类型
                value = cell.getBooleanCellValue() + "";
                break;
            case BLANK://空值
                value = "";
                break;
            case ERROR://错误类型
                value = "非法字符";
                break;
            default:
                value = "未知类型";
        }
    }
    return value.trim();
}

public class JsonResult implements Serializable {

    private String resultCode;

    private String resultMsg;

    private Object data;

    public JsonResult(String code, String msg) {
        this.resultCode = code;
        this.resultMsg = msg;
    }

    public JsonResult(String code, String msg, Object data) {
        this.resultCode = code;
        this.resultMsg = msg;
        this.data = data;
    }


    public static JsonResult build(ResultCode resultCode){
        return new JsonResult(resultCode.getCode(), resultCode.getMsg());
    }

    public static JsonResult build(ResultCode resultCode, String msg){
        return new JsonResult(resultCode.getCode(), resultCode.getMsg()+" "+msg);
    }

    public static JsonResult success() {
        return JsonResult.build(ResultCode.SUCCESS);
    }

    public static JsonResult success(Object object) {
        return new JsonResult(ResultCode.SUCCESS.getCode(), ResultCode.SUCCESS.getMsg(),object);
    }

    public static JsonResult parameterError(String msg){
        return JsonResult.build(ResultCode.ARGUMENTS_ERROR,msg);
    }

}