Image not displaying in JSP (Spring MVC) local file

My Image is not showing in my JSP. It shows as a broken image and the html returns a error 500

This is the code for my JSP

<td style="padding: 25px;">
                <a href="CompositeDetails?caseNo=${photo.caseNo}"> <img src="imageDisplay?caseNo=${photo.caseNo}" width="120"/></a>
            </td>  

here is my controller for imageDisplay

    @RequestMapping(value = "/imageDisplay", method = RequestMethod.GET)
public void showImage(@RequestParam("caseNo") String caseNo, HttpServletResponse response, HttpServletRequest request) throws IOException {
    GalleryResults gr = galleryService.getCompositeSketch(caseNo);

    FileInputStream fileInputStream = new FileInputStream(gr.getPhotoLocation());
    byte[] bytes = IOUtils.toByteArray(fileInputStream);

    response.setContentType("image/jpeg, image/jpg, image/png, image/gif");

    response.getOutputStream().write(bytes);
    response.getOutputStream().close();
}

my query there returns the location as: C:\Files\*.png

Yes, the picture is in my drive.