HSSFHyperlink and URL fragment encoding

I am using the apache poi package to generate excel workbooks. In the workbook I include cells with hyperlinks, using URLs containing fragments (#frag). In the resulting cells, the # character in the url has been encoded which makes it a different URL.

My question: Is there any way to preserve the URL provided as is?

My code:

        Cell cell = row.createCell(index);
        cell.setCellValue("the link");
        HSSFHyperlink link = workbook.getCreationHelper().createHyperlink(HSSFHyperlink.LINK_URL);
        link.setAddress("http://localhost:3000/#/search/pattern");
        cell.setHyperlink(link);

The url opened in the browser after clicking on the link in the generated spreadsheet

http://localhost:3000/%23/search/pattern

Any pointer appreciated.