Spring Boot Controller export an Excel

Question

I have a java/spring boot application where I want to build an API endpoint that creates and returns a downloadable excel file. Here is my controller endpoint:

@         


        

Answer 1

You have to set the file name to the response header using Content-disposition. Try this

@GetMapping("/export")
public ResponseEntity export(HttpServletResponse response) {
        fooService.export(response);      
}

Change your service method like this

public Resource export(HttpServletResponse response) throws IOException {
    StringBuilder filename = new StringBuilder("Foo Export").append(" - ")
                                                        .append("Test 1.xlsx");
   return export(filename, response);
}

private void export(String filename,  HttpServletResponse response) throws IOException {
      try (Workbook workbook = generateExcel()) {
          FileOutputStream fos = write(workbook, filename);
          IOUtils.copy(new FileInputStream(fos.getFD()),               
                                     servletResponse.getOutputStream());//IOUtils is from apache commons io
          response.setContentType("application/vnd.ms-excel");
          response.setHeader("Content-disposition", "attachment; filename=" + filename);
     }catch(Exception e) {
       //catch if any checked exception
     }finally{
        //Close all the streams
     }
}