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servlet is showing java.io.FileNotFoundException: ?E:\guru99\test.txt (The filename, directory name, or volume label syntax is incorrect)

My servlet is showing this exception but the file exist at that location.
java.io.FileNotFoundException: ?E:\guru99\test.txt (The filename, directory name, or volume label syntax is incorrect)
Servlet Code,
#WebServlet(urlPatterns = {"/image_download"})
public class image_download extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String gurufile = "test.txt";
String gurupath = "‪E:\\guru99\\";
response.setContentType("APPLICATION/OCTET-STREAM");
response.setHeader("Content-Disposition", "attachment; filename=\"" + gurufile + "\"");
FileInputStream fileInputStream = new FileInputStream(gurupath + gurufile);
int i;
while ((i = fileInputStream.read()) != -1) {
out.write(i);
}
fileInputStream.close();
out.close();
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
I want to download the file from the link I provided.

Your issue is duplicate of this SO question
As when I tried to copy your code to my eclipse , I got same prompt about Save Problems. Somewhere there is an invalid character & string with that char can't be parsed into valid file path.
I manually retyped values for String gurufile & String gurupath instead of copy pasting your code & it worked successfully. Culprit seems String gurupath.
Second point is usage of try-with-resource ( though that has nothing to do with your issue ) instead of explicitly trying to close out resources,
response.setContentType("text/html");
String gurufile = "test.txt";
String gurupath = "D:\\guru99\\";
response.setContentType("APPLICATION/OCTET-STREAM");
response.setHeader("Content-Disposition", "attachment; filename=\"" + gurufile + "\"");
try (FileInputStream fileInputStream = new FileInputStream(gurupath + gurufile);
PrintWriter out = response.getWriter();) {
int i;
while ((i = fileInputStream.read()) != -1) {
out.write(i);
}
}
Copy - paste my code to see if this resolves your problem.

how to add metadata to file when uploading to google-cloud-storage via appengine

I'm uploading a file to GCS via app-engine following the docs
(the code was taken from here)
public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
GcsFileOptions instance = GcsFileOptions.getDefaultInstance();
GcsFilename fileName = getFileName(req);
GcsOutputChannel outputChannel;
outputChannel = gcsService.createOrReplace(fileName, instance);
copy(req.getInputStream(), Channels.newOutputStream(outputChannel));
}
and here is the copy method:
private void copy(InputStream input, OutputStream output) throws IOException {
try {
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = input.read(buffer);
while (bytesRead != -1) {
output.write(buffer, 0, bytesRead);
bytesRead = input.read(buffer);
}
} finally {
input.close();
output.close();
}
}
now I want to add this metadata to the file
metadata = "{timestamp:\"01/12/2016\", blabla: 111}"
How do I add this metadata using the code above?

use new Builder().addUserMetadata() insted of GcsFileOptions.getDefaultInstance();
public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
GcsFileOptions instance = new Builder().addUserMetadata("timestamp", "01/12/2016").build();
GcsFilename fileName = getFileName(req);
GcsOutputChannel outputChannel;
outputChannel = gcsService.createOrReplace(fileName, instance);
copy(req.getInputStream(), Channels.newOutputStream(outputChannel));
}

Java GWT cannot open downloaded xlsx file

I'm new to GWT and in my company i was asked to make some changes in one of our applications.
Currently the Program generates reports in .xls format. Now we want to change it to .xlsx
public class Download extends HttpServlet {
private static final long serialVersionUID = 5580666921970339383L;
#Override
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
#Override
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String filename = (String)request.getSession().getAttribute(CrossReportConstants.ATTR_FILENAME);
byte[] data = (byte[])request.getSession().getAttribute(CrossReportConstants.ATTR_REPORT);
request.getSession().setAttribute(CrossReportConstants.ATTR_FILENAME, null);
request.getSession().setAttribute(CrossReportConstants.ATTR_REPORT, null);
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-Disposition", "attachment;filename=" + filename);
response.setHeader("Pragma", "no-cache");
response.setHeader("Expires", "0");
response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate");
response.setContentLength(data.length);
try {
InputStream in = new ByteArrayInputStream(data);
ServletOutputStream out = response.getOutputStream();
byte[] outputByte = new byte[4096];
// copy binary contect to output stream
while (in.read(outputByte, 0, 4096) != -1) {
out.write(outputByte, 0, 4096);
}
in.close();
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
I changed response.setContentType("application/vnd.ms-excel"); to
response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
and I changed the filename to exampleReport.xlsx
When i test the Application i can download the report but i cannot open it - Excel tells me the file is corrupted. (the file has the right size and when i open it in a text editor i can see the content)
Did I miss something?
Thanks in advance

MSWord File download issue using HttpServlet

i have implemented a servlet to download doc files available under my application classpath.
what happening is; file is downloading but ms-word is unable to open it property.
see the screenshot of ms-word:
Servlet implementation is as follows:
public class DownloadFileServlet extends HttpServlet {
protected void doGet(
HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String fileName = "test.doc";
ClassPathResource resource = new ClassPathResource(File.separator + fileName);
ServletOutputStream sos = null;
FileInputStream fis = null;
try {
response.setContentType("application/msword");
response.setHeader("Content-disposition", "attachment; fileName=\"" + fileName + "\"" );
fis = new FileInputStream(new File(resource.getURI().getPath()));
byte[] bytes = org.apache.commons.io.IOUtils.toByteArray(fis);
sos = response.getOutputStream();
sos.write(bytes);
sos.flush();
} catch (Exception e) {
e.printStackTrace();
} finally {
if( fis != null) {
fis.close();
}
if( sos != null) {
sos.close();
}
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
i have tried almost all suggested Content Types for ms-word files. but still it is not working.
application/msword
application/ms-word
application/vnd.ms-word
Kindly suggest I'm making a mistake or is there any other way to achieve.
Note: i have tried almost all approaches available on SO.

Instead of reading, converting to byte[] simply write directly to the OutputStream. You shouldn't close the OutputStream as that is being handled by the container for you.
I would rewrite your servlet method to more or less the following (also why is it a servlet and not a (#)Controller?
protected void doGet(
HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String fileName = "test.doc";
ClassPathResource resource = new ClassPathResource(File.separator + fileName);
InputStream input = resource.getInputStream();
try {
response.setContentType("application/msword");
response.setHeader("Content-disposition", "attachment; fileName=\"" + fileName + "\"" );
org.springframework.util.StreamUtils.copy(input, response.getOutputStream());
} catch (Exception e) {
e.printStackTrace();
} finally {
if (input != null) {
try {
input.close();
} catch (IOEXception ie) {}
}
}
}

i do not know what a ClassPathResource class does. hence modified the code a bit.
ClassLoader clsLoader = Thread.currentThread().getContextClassLoader();
InputStream is = clsLoader.getResourceAsStream("test.doc");
and in the try block use:
byte[] bytes = org.apache.commons.io.IOUtils.toByteArray(is);
this should work fine. i placed the doc in the classpath. modify it to suit your needs.
Regarding the mime mapping, open your server properties and you will find a list of mime mapping. Eg. in eclipse for tomcat, just double click on the server and you should be able to find the mime mapping list there. application/msword worked fine

Why does my browser receive no data when OutputStream.flush() is called?

I have a servlet which just read a file and send it to the browser.
The file is readen correctly, but on OutputStream.flush(), the browser receive no data.
Firefox says :
"Corrupted Content Error
The page you are trying to view cannot be shown because an error in the data transmission was detected.". Firebug shows the status "Aborted".
IE open or save an empty file.
I tried little or big files.
The code is :
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
* #param request servlet request
* #param response servlet response
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// Use a ServletOutputStream because we may pass binary information
response.reset();
OutputStream out = response.getOutputStream();
// Get the file to view
String file = request.getParameter("path");
// Get and set the type and size of the file
String contentType = getServletContext().getMimeType(file);
response.setContentType(contentType);
long fileSize = (new File(file)).length();
response.setHeader("Content-Length:", "" + fileSize);
File f = new File(file);
response.setHeader("Content-Disposition", "attachment;filename="+f.getName());
response.setContentLength((int) fileSize);
// Return the file
try {
returnFile(file, out, response);
} catch (Exception e) {
Logger.getLogger(AffichageItemsServlet.class).error("", e);
} finally {
out.close();
}
}
// Send the contents of the file to the output stream
public static void returnFile(String filename, OutputStream out, HttpServletResponse resp)
throws FileNotFoundException, IOException {
FileInputStream fis = null;
try {
fis = new FileInputStream(filename);
byte[] buff = new byte[8* 1024];
int nbRead = 0;
while ((nbRead = fis.read(buff, 0, buff.length)) !=-1) {
out.write(buff, 0, nbRead);
}
out.flush();
} finally {
if (fis != null) {
fis.close();
}
}
}
The response is sent on "out.flush".
Any idea ?

For one thing, remove this line (you call setContentLength() below that):
response.setHeader("Content-Length:", "" + fileSize);
Also, you might try moving the getOutputStream() call to just before you start using the stream.