public ResponseEntity<Object> importPcpXlsx(MultipartFile xlsx) {
      try {
        XSSFWorkbook xssfWorkbook = new XSSFWorkbook(xlsx.getInputStream());
        XSSFSheet xssfSheet = xssfWorkbook.getSheetAt(0);
        Row row;
        Cell cell;
        int i = 1;
      
        List<String> number = new ArrayList<>();
        while (true) {
         if (xssfSheet.getRow(i) != null) {
           row = xssfSheet.getRow(i);
           cell = row.getCell(0);
 
           if (cell.getSheet()
              .getRow(0)
              .getCell(0)
              .getRichStringCellValue()
              .getString()
              .equals("Number".trim())) {
            
             number.add(cell.getStringCellValue().trim());
 
             log.info("number: "   i   ".  № "   cell.getStringCellValue());
           }
         } else {
           i = 1;
           break;
         }
         i  ;
        }
     
        List<String> kpgz = new ArrayList<>();
        while (true) {
          if (xssfSheet.getRow(i) != null) {
          
            row = xssfSheet.getRow(i);
            cell = row.getCell(1);
 
            if (cell.getSheet()
               .getRow(0)
               .getCell(1)
               .getRichStringCellValue()
               .getString()
               .equals("kpgz".trim())) {
 
             kpgz.add(cell.getStringCellValue().trim());
 
             log.info("kpgz: "   i   ". "   cell.getStringCellValue());
           }
         } else {
           i = 1;
           break;
         }
         i  ;
       }

I go through the columns and read all the lines under each column. But what if I have some columns will not come in xlxs file. That is, I need an option where I do not have to strictly specify columns. Please predict. In code Iread by columns, since columns have different types and should be processed differently. I need to do this so that I do not specify the number of columns in the column number code, as I did cell = row.getCell(0); or row.getCell(1) or row.getCell(2)

CodePudding user response：

Read the columns one by one and bind their type, then check data under these columns.

See example of type checking there: Best language to parse extremely large Excel 2007 files

If you can definetely identify column, it is not a problem. If not, you should think about changing api.