import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.DataFormat;
public class PoiTest {
public static void main(String[] args) throws IOException {
HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
HSSFRow row = sheet.createRow(0);
// Create a cell and put a date value in it. The first cell is not
// styled as a date.
HSSFCell cell = row.createCell(0);
cell.setCellValue(new Date());
// we style the second cell as a date (and time). It is important to
// create a new cell style from the workbook
// otherwise you can end up modifying the built in style and effecting
// not only this cell but other cells.
HSSFCellStyle cellStyle = wb.createCellStyle();
DataFormat df = wb.createDataFormat();
// cellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("m/d/yy"));
cellStyle.setDataFormat(df.getFormat("YYYY-MM-DD HH:MM:SS"));
cell = row.createCell(1);
cell.setCellValue(new Date());
cell.setCellStyle(cellStyle);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("src/test/resources/workbook.xls");
wb.write(fileOut);
fileOut.close();
}