private Format getFormat(Cell cell, ConditionalFormattingEvaluator cfEvaluator) {
        if (cell == null) {return null;}

        ExcelNumberFormat numFmt = ExcelNumberFormat.from(cell, cfEvaluator);

        if (numFmt == null) {
            return null;
        }

        int formatIndex = numFmt.getIdx();
        String formatStr = numFmt.getFormat();
        if (formatStr == null || formatStr.trim().length() == 0) {
            return null;
        }
        return getFormat(cell.getNumericCellValue(), formatIndex, formatStr);
    }
Return a Format for the given cell if one exists, otherwise try to create one. This method will return
<code>null</code> if the any of the following is true:
<ul>
<li>the cell's style is null</li>
<li>the style's data format string is null or empty</li>
<li>the format string cannot be recognized as either a number or date</li>
</ul>

@param cell The cell to retrieve a Format for
@return A Format for the format String
fastexcel-test/src/test/java/cn/idev/excel/test/temp/dataformat/DataFormatter1.java