I want to create an Excel file from a method in Java and download it in a browser.
I have found an example on this post where you create the Excel file, but I want to create the .xls file and download it from a web browser.
How can I do that?
-
1Do you mean you would like to download the file in a web browser? Or you would like to visualize the excel file in a web browser?pmartin8– pmartin82015-09-23 16:00:07 +00:00Commented Sep 23, 2015 at 16:00
-
Just download the created file in a location in my PC, just like a regular download...CyborgNinja23– CyborgNinja232015-09-23 16:02:02 +00:00Commented Sep 23, 2015 at 16:02
-
1Where will the file be? Locally on your machine, or somewhere on a server?pmartin8– pmartin82015-09-23 16:09:19 +00:00Commented Sep 23, 2015 at 16:09
-
Locally in my machine...CyborgNinja23– CyborgNinja232015-09-23 16:10:09 +00:00Commented Sep 23, 2015 at 16:10
-
Just type this in your browser : file:///C:/path_to_your_file.xls then you will download the file... It has nothing to do with Java or Excel though.pmartin8– pmartin82015-09-23 16:12:26 +00:00Commented Sep 23, 2015 at 16:12
|
Show 2 more comments
3 Answers
I finally found a solution for my problem...!!
This is working for me:
@RequestMapping("/downloadFile")
public void downloadFile(HttpServletRequest request, HttpServletResponse response) {
try {
String fileName = "C:/excelFile.xls";
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet("firstSheet");
HSSFRow rowhead = sheet.createRow((short) 0);
rowhead.createCell(0).setCellValue("No.");
rowhead.createCell(1).setCellValue("Name");
rowhead.createCell(2).setCellValue("Address");
rowhead.createCell(3).setCellValue("Email");
HSSFRow row = sheet.createRow((short) 1);
row.createCell(0).setCellValue("1");
row.createCell(1).setCellValue("Carlos");
row.createCell(2).setCellValue("Costa Rica");
row.createCell(3).setCellValue("[email protected]");
FileOutputStream fileOut = new FileOutputStream(fileName);
workbook.write(fileOut);
fileOut.close();
System.out.println("Your excel file has been generated!");
//Code to download
File fileToDownload = new File(fileName);
InputStream in = new FileInputStream(fileToDownload);
// Gets MIME type of the file
String mimeType = new MimetypesFileTypeMap().getContentType(fileName);
if (mimeType == null) {
// Set to binary type if MIME mapping not found
mimeType = "application/octet-stream";
}
System.out.println("MIME type: " + mimeType);
// Modifies response
response.setContentType(mimeType);
response.setContentLength((int) fileToDownload.length());
// Forces download
String headerKey = "Content-Disposition";
String headerValue = String.format("attachment; filename=\"%s\"", fileToDownload.getName());
response.setHeader(headerKey, headerValue);
// obtains response's output stream
OutputStream outStream = response.getOutputStream();
byte[] buffer = new byte[4096];
int bytesRead = -1;
while ((bytesRead = in.read(buffer)) != -1) {
outStream.write(buffer, 0, bytesRead);
}
in.close();
outStream.close();
System.out.println("File downloaded at client successfully");
} catch (Exception ex) {
System.out.println(ex);
}
}
Comments
If you want to trigger a Java process from a Web Browser (HTTP request), then you need an application server (like Tomcat) to accept your HTTP request and execute some server-side code (Servlet). A main method like in the example cannot be launched by a HTTP request. Look here if you never wrote a Servlet before.
1 Comment
pmartin8
Now, you see how important it is to be clear in the original question.
This has nothing to do with Excel, but this post shows how to download a file from a Spring MVC controler.
@RequestMapping(value = "/files/{file_name}", method = RequestMethod.GET)
public void getFile(@PathVariable("file_name") String fileName, HttpServletResponse response) {
try {
// get your file as InputStream
InputStream is = ...;
// copy it to response's OutputStream
org.apache.commons.io.IOUtils.copy(is, response.getOutputStream());
response.flushBuffer();
} catch (IOException ex) {
log.info("Error writing file to output stream. Filename was '{}'", fileName, ex);
throw new RuntimeException("IOError writing file to output stream");
}
}