apache poi写HH:mm:ss字符串到Excel时间数据类型

Question

我使用apache poi将CSV文件重写为Excel,对于任何字符串,如HH:mm:ss,我需要将其转换为适当的Excel数据类型,以便用户可以对该列应用sum()函数.我尝试了不同的数据类型,但是当我打开excel文件时,我无法对该列求和,总和显示为"0:00:00",即使在Excel中单击该列显示为"时间"数据类型,

这是我的代码:

CreationHelper creationHelper = workbook.getCreationHelper();
HSSFCellStyle timeStyle = workbook.createCellStyle();          
timeStyle.setDataFormat(creationHelper.createDataFormat().getFormat("h:mm:ss"));
cell.setCellValue(column);
if (isTime(column)) {
  cell.setCellStyle(timeStyle);
}

private boolean isTime(String value) {
        try {
            dtf.parseDateTime(value);
            return true;
        } catch (IllegalArgumentException e) {
            return false;
        }
    }

这是我的excel文件

Answer 1

如果column代码中的对象是String,那么单元格的内容将始终是字符串(文本)单元格内容之后cell.setCellValue(column).这个功能SUM无法使用的内容.这些功能需要数字内容.在Excel日期和时间也是仅格式化为日期时间的数字内容.使用默认设置1 = 1天= 01/01/1900 00:00:00.1小时= 1/24,1分钟= 1/24/60,1秒= 1/24/60/60.

如果column是格式为"HH:MM:SS"的字符串,则可以使用DateUtil.convertTime将此字符串转换为Excel有价值的时间.

完整示例显示哪些不起作用,哪些起作用:

import java.io.FileOutputStream;

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.DateUtil;

public class ExcelCalculateTimeValues {

 public static void main(String[] args) throws Exception {

  Workbook workbook = new HSSFWorkbook();
  //Workbook workbook = new XSSFWorkbook();

  CreationHelper createHelper = workbook.getCreationHelper();
  CellStyle styletime = workbook.createCellStyle();
  styletime.setDataFormat(createHelper.createDataFormat().getFormat("hh:mm:ss"));

  Sheet sheet = workbook.createSheet();
  sheet.createRow(0).createCell(0).setCellValue("Time sting");
  sheet.getRow(0).createCell(1).setCellValue("Time");

  String[][] tableData = new String[][]{
   {"12:34:00", "22:45:00"},
   {"23:45:05", "01:34:40"},
   {"08:01:00", "13:23:00"},
   {"15:41:12", "23:23:22"}
  };

  int r = 1;
  for (String[] rowData : tableData) {
   Row row = sheet.createRow(r++);
   int c = 0;
   for (String cellData : rowData) {
    Cell cell = row.createCell(c);
    if (c == 0 ) {
     cell.setCellValue(cellData); //this sets string cell data
    } else if (c == 1) {
     cell.setCellValue(DateUtil.convertTime(cellData)); //this sets datetime cell data
    }
    cell.setCellStyle(styletime);
    c++;
   }
  }

  sheet.createRow(r).createCell(0).setCellFormula("SUM(A2:A"+r+")"); //cannot work because of string values in A2:A4
  sheet.getRow(r).createCell(1).setCellFormula("SUM(B2:B"+r+")"); //will work

  workbook.setForceFormulaRecalculation(true);

  if (workbook instanceof HSSFWorkbook) {
   workbook.write(new FileOutputStream("ExcelCalculateTimeValues.xls"));
  } else if (workbook instanceof XSSFWorkbook) {
   workbook.write(new FileOutputStream("ExcelCalculateTimeValues.xlsx"));
  }
  workbook.close();

 }

}