At first you need to know how to use DataFormats. Then you need to know the guidelines for customizing a number format.
For your number -337499.939437217
which will be displayed rounded with general number format, you could use format #.###############
. The #
means a digit which will be displayed only if needed (is not leading zero and/or is not zero as last decimal digit) - see guidelines. So the whole format means show up to 15 decimal digits if needed but only as much as needed.
For currency you should really using a built in number format for currency. So the currency symbol depends on the locale settings of Excel
. The following BuiltinFormats are usable with apache poi
. Using a built in number format you need only the hexadecimal format numbers.
Example:
import java.io.*;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class CreateNumberFormats {
public static void main(String[] args) throws Exception {
Workbook wb = new XSSFWorkbook();
Sheet sheet = wb.createSheet("format sheet");
CellStyle style;
DataFormat format = wb.createDataFormat();
Row row;
Cell cell;
short rowNum = 0;
short colNum = 0;
row = sheet.createRow(rowNum++);
cell = row.createCell(colNum);
cell.setCellValue(-337499.939437217); // general format
style = wb.createCellStyle();
style.setDataFormat(format.getFormat("#.###############")); // custom number format
row = sheet.createRow(rowNum++);
cell = row.createCell(colNum);
cell.setCellValue(-337499.939437217);
cell.setCellStyle(style);
row = sheet.createRow(rowNum++);
cell = row.createCell(colNum);
cell.setCellValue(123.456789012345);
cell.setCellStyle(style);
row = sheet.createRow(rowNum++);
cell = row.createCell(colNum);
cell.setCellValue(123456789.012345);
cell.setCellStyle(style);
style = wb.createCellStyle();
style.setDataFormat((short)0x7); // builtin currency format
row = sheet.createRow(rowNum++);
cell = row.createCell(colNum);
cell.setCellValue(-1234.5678);
cell.setCellStyle(style);
sheet.autoSizeColumn(0);
FileOutputStream fileOut = new FileOutputStream("CreateNumberFormats.xlsx");
wb.write(fileOut);
fileOut.close();
wb.close();
}
}