Spring - Download excel with POI - spring-mvc

Question

I have this controller which create an empty sheet and I want to return the excel file to the navigator. The problem is, the excel file is corrupted.
If I create the file on my computer the file isn't corrupted, so my HSSFWorkbook is valid. Seems a problem of encodage/encapsulation added by the spring context ?
#Controller
public class ExportController {
#RequestMapping(value = "/export/test/excel", method = RequestMethod.POST)
public void downloadExcelTestFile(
HttpServletRequest request,
HttpServletResponse response) throws IOException {
HSSFWorkbook wb = new HSSFWorkbook();
wb.createSheet("Sheet1");
//response.reset();
//response.setStatus(HttpServletResponse.SC_OK);
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-Disposition", "attachment; filename=test.xls");
OutputStream out = response.getOutputStream();
wb.write(out);
out.flush();
out.close();
wb.close();
}
The download start well, I receive the file test.xls, but I can't open it. Is there a Spring way to achiev a proper download inside a #Controller ?
I use Spring 4.2.4
UPDATE 1
I tried a Spring way but it's not working better
HSSFWorkbook wb = new HSSFWorkbook();
wb.createSheet("Sheet1");
ByteArrayOutputStream bos = new ByteArrayOutputStream();
try {
wb.write(bos);
} finally {
bos.close();
}
byte[] bytes = bos.toByteArray();
HttpHeaders headers = new HttpHeaders();
headers.set("Content-Type", "application/vnd.ms-excel;");
headers.set("content-length",Integer.toString(bytes.length));
headers.set("Content-Disposition", "attachment; filename=test.xls");
return new ResponseEntity<byte[]>(bytes, headers, HttpStatus.CREATED);
UPDATE 3
I found a reason but I don't understand why.
If I build my war file and deploy it manually in the very same tomcat 7.0.70 it works. My Excel is not corrupted.
If I download from the dev environnement in eclipse, it doesn't work. Seems a tomcat + eclipse issue.

Answer 1

Ok that wasn't a Spring issue, not even a tomcat issue.
The problem was from my grunt-connect-proxy, when I run my front throught localhost:9000 : files that I downloaded were corrupted. If I build the project in a war file or run the front from localhost:8080 ( same port than the server ) without "grunt serve" and so without the proxy it works.
I have not fix the problem with grunt ... I just ignore it, but this answer can save your time.

Answer 2

Sample Spring Backed Code to create an excel and return it using Spring REST. The input parameters may change as per your requirement
#RequestMapping(value = "/convertFlatFileToExcel.do", method = RequestMethod.POST)
public HttpEntity<byte[]> convertFlatFileToExcel(#RequestParam(value="file") MultipartFile file,#RequestParam(value="jobid") String jobid) {
ByteArrayOutputStream archivo = new ByteArrayOutputStream();
XSSFWorkbook workbook = new XSSFWorkbook();
workbook.write(archivo);
if(null!=workbook && null!=archivo) {
workbook.close();
archivo.close();
}
byte[] documentContent = archivo.toByteArray();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.parseMediaType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"));
headers.set(HttpHeaders.CONTENT_DISPOSITION, "inline; filename=\"myexcelfile.xls\"");
headers.setContentLength(documentContent.length);
response = new ResponseEntity<byte[]>(documentContent, headers, HttpStatus.OK);
}
**Sample UI Code:
Below is the sample code to call to Rest Service using Angular JS. Import the FileSaver js file using https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/2014-11-29/FileSaver.min.js
This will have the method saveAs() to save the given excel blob data with a given name.
**
$http.post(urlBase+'/convertFlatFileToExcel.do', formData,{
transformRequest : angular.identity,
responseType: 'arraybuffer',
headers : {
'Content-Type' : undefined,
'Accept': 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'
}})
.then(
function (response) {
$window.sessionStorage.showProgress = "";
var file = new Blob([response.data], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"});
saveAs(file, jobid.toUpperCase()+'.xlsx');
},
function (errResponse) {
$window.sessionStorage.showProgress = "";
$mdDialog.show($mdDialog.alert({title: 'Invalid Job ID!',textContent: 'Please enter a valid Job ID. For any issues, please contact the admin!',ok: 'GOT IT!'}));
deferred.reject(errResponse);
});