Reputation: 175
Following is my code:
String monthEndDate = "31-Dec-17";
SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yy",java.util.Locale.ENGLISH);
XSSFCell updateDateCell = sheet.getRow(rownumber).getCell(15);
XSSFCellStyle cellStyle = (XSSFCellStyle)updateDateCell.getCellStyle();
CreationHelper createHelper = wb.getCreationHelper();
cellStyle.setDataFormat(
createHelper.createDataFormat().getFormat("dd-MMM-yy"));
Date updateDate = sdf.parse(monthEndDate);
updateDateCell.setCellValue(updateDate);
updateDateCell.setCellStyle(cellStyle);
It is setting numeric value 43100.0
Upvotes: 1
Views: 1479
Reputation: 3733
This is an example which I already have for formatting date, you can reuse the part of it ( I marked the relevant lines of code). It's tested and working fine, if any issue let me know.
//UPDATE Please see Axel Richter's answer https://stackoverflow.com/a/47920182/1053496 for the correct answer. In my example, I'm storing date as String instead of Date object which is not the recommended way
import org.apache.poi.ss.usermodel.DataFormat;
import org.apache.poi.xssf.usermodel.*;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
public class WriteExcelBasic {
public static void main(String[] args) throws IOException {
String excelFileName = "/Users/home/Test3.xls";
FileOutputStream fos = new FileOutputStream(excelFileName);
XSSFWorkbook wb = new XSSFWorkbook();
XSSFCellStyle style = wb.createCellStyle();
XSSFSheet sheet = wb.createSheet("sheet");
XSSFFont urlFont = wb.createFont();
style.setFont(urlFont);
String monthEndDate = "31-Dec-17";
DataFormat df = wb.createDataFormat(); //these 3 lines are enough
short dateFormat = df.getFormat("dd-MMM-yy"); // 2nd
style.setDataFormat(dateFormat); // 3rd
for (int r = 0; r < 1; r++) {
XSSFRow row = sheet.createRow(r);
row.setHeight((short) -1);
for (int c = 0; c < 3; c++) {
XSSFCell cell = row.createCell(c);
String ss = "31-Dec-17";
cell.setCellValue(ss);
style.setWrapText(true);
cell.setCellStyle(style);
}
}
try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
wb.write(baos);
byte[] myByteArray = baos.toByteArray();
fos.write(myByteArray);
fos.flush();
}
finally {
wb.close();
fos.close();
}
}
}
Upvotes: 0
Reputation: 61890
I suspect your problem is that you are getting the CellStyle
via Cell.getCellStyle
and then you are overwriting that CellStyle
.
CellStyle
s are in Excel
defined on Workbook
level. That means, not each cell has it's own cell style but cells share cell styles defined on workbook level.
So if you do the getting the CellStyle
via Cell.getCellStyle
and then overwriting that CellStyle
multiple times then only the last overwriting will be active. So I suspect, your complete code overwrites the same cell style, gotten from another cell, with another number format after you have overwritten it with the date number format.
The easy conclusion could be to really give each cell it's own cell style. But this is also wrong since there is a limit number of cell styles in a workbook. So we need
To achieve this CellUtil can be used in apache poi
. This provides methods only to create a new cell style if there is not already the same cell style defined in the workbook and simply to use that cell style if there is already the same cell style defined in the workbook.
Example:
import java.io.*;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.*;
import org.apache.poi.ss.util.CellUtil;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Map;
import java.util.HashMap;
public class ExcelSetDateValue {
public static void main(String[] args) throws Exception {
XSSFWorkbook wb = (XSSFWorkbook)WorkbookFactory.create(new FileInputStream("ExcelTest.xlsx"));
//possiby we need data formats
DataFormat dataFormat = wb.createDataFormat();
//get sheet and set row number
XSSFSheet sheet = wb.getSheetAt(0);
int rownumber = 3;
//get the date
String monthEndDate = "31-Dec-17";
SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yy", java.util.Locale.ENGLISH);
Date updateDate = sdf.parse(monthEndDate);
//set date as cell value
XSSFCell updateDateCell = sheet.getRow(rownumber).getCell(15);
updateDateCell.setCellValue(updateDate);
//use CellUtil to set the CellStyleProperties
Map<String, Object> properties = new HashMap<String, Object>();
properties.put(CellUtil.DATA_FORMAT, dataFormat.getFormat("dd-MMM-yy"));
CellUtil.setCellStyleProperties(updateDateCell, properties);
wb.write(new FileOutputStream("ExcelTestNew.xlsx"));
wb.close();
}
}
Upvotes: 2
Reputation: 43585
Add updateDateCell = Format(updateDateCell, "dd-MMM-yyyy")
at the end of your code.
You should get 31-Dec-2017
.
Upvotes: 0