POI 合并单元格

private void mergedCell(Sheet sheet, int firstRow, int lastRow, int firstCol, int lastCol, Object value) {
    CellRangeAddress region = new CellRangeAddress(firstRow, lastRow, firstCol, lastCol);
    sheet.addMergedRegion(region);
    Row row = sheet.createRow(firstRow);
    Cell cell = row.createCell(firstCol);
    if (value instanceof Integer) {
        cell.setCellValue((Integer) value);
    } else if (value instanceof String) {
        cell.setCellValue((String) value);
    } else if (value instanceof Double) {
        cell.setCellValue((Double) value);
    } else if (value instanceof Boolean) {
        cell.setCellValue((Boolean) value);
    } else if (value instanceof LocalDate) {
        cell.setCellValue((LocalDate) value);
    } else if (value instanceof LocalDateTime) {
        cell.setCellValue((LocalDateTime) value);
    } else if (value instanceof RichTextString) {
        cell.setCellValue((RichTextString) value);
    } else if (value instanceof Calendar) {
        cell.setCellValue((Calendar) value);
    } else {
        cell.setCellValue((String) value);
    }

}