I am trying to send the contents of an XML file from a handheld device (Compact Framework/Windows CE) to a Web API method in my server app like so (Client code):
public static string SendXMLFile(string xmlFilepath, string uri, int timeout)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.KeepAlive = false;
request.ProtocolVersion = HttpVersion.Version10;
request.Method = "POST";
StringBuilder sb = new StringBuilder();
using (StreamReader sr = new StreamReader(xmlFilepath))
{
String line;
while ((line = sr.ReadLine()) != null)
{
// test to see if it's finding any lines
//MessageBox.Show(line); <= works fine
sb.AppendLine(line);
}
byte[] postBytes = Encoding.UTF8.GetBytes(sb.ToString());
if (timeout < 0)
{
request.ReadWriteTimeout = timeout;
request.Timeout = timeout;
}
request.ContentLength = postBytes.Length;
request.KeepAlive = false;
request.ContentType = "application/xml";
try
{
Stream requestStream = request.GetRequestStream();
requestStream.Write(postBytes, 0, postBytes.Length);
requestStream.Close();
using (var response = (HttpWebResponse)request.GetResponse())
{
return response.ToString();
}
}
catch (Exception ex)
{
MessageBox.Show("SendXMLFile exception " + ex.Message);
request.Abort();
return string.Empty;
}
}
}
As you can see in the commented out code ("<= works fine"), I've tested it and the data I want is being added to the StringBuilder. There is no exception being thrown (I don't see "SendXMLFile exception ").
However, when the corresponding server code is called:
[Route("api/DeliveryItems/PostArgsAndXMLFileAsStr")]
public async void PostArgsAndXMLFileAsStr([FromBody] string stringifiedXML, string serialNum, string siteNum)
{
string beginningInvoiceNum = string.Empty;
string endingInvoiceNum = string.Empty;
XDocument doc = XDocument.Parse(stringifiedXML);
...the "serialNum" and "siteNum" args are as expected (contain the valid expected values) but the body (stringifiedXML) is null. Why?
UPDATE
I added this, too, in the client:
request.ContentLength = postBytes.Length;
// Did the sb get into the byte array?
MessageBox.Show(request.ContentLength.ToString());
...and the byte array does have the data, as it shows me "112" (the XML file is quite small).
UPDATE 2
Now I added yet another debug msg:
try
{
Stream requestStream = request.GetRequestStream();
// now test this:
MessageBox.Show(string.Format("requestStream length is {0}", requestStream.Length.ToString()));
requestStream.Write(postBytes, 0, postBytes.Length);
requestStream.Close();
using (var response = (HttpWebResponse)request.GetResponse())
{
return response.ToString();
}
}
catch (Exception ex)
{
MessageBox.Show("SendXMLFile exception " + ex.Message);
request.Abort();
return string.Empty;
}
...and I don't even see the "requestStream length is" message; instead I see, "SendXMLFileException NotSupportedException"...???
UPDATE 3
I guess this is an example of the Hawthorn Effect or similar. Once I commented out that debug (MessageBox.Show()) statement, I'm back to making it into the server app, but with the [FromBody] val null.
Then the client has the message, "Unable to read data from the transport connection"
UPDATE 4
stringifiedXML is still null here:
public async void PostArgsAndXMLFileAsStr([FromBody] string stringifiedXML, string serialNum, string siteNum)
{
string beginningInvoiceNum = string.Empty;
string endingInvoiceNum = string.Empty;
XDocument doc = XDocument.Parse(stringifiedXML);
...even after I modified the code in the client following a response to this question like so:
public static string SendXMLFile(string xmlFilepath, string uri)
{
MessageBox.Show(string.Format("In SendXMLFile() - xmlFilepath == {0}, uri == {1}", xmlFilepath, uri));
string strData = GetDataFromXMLFile();
HttpWebRequest request = CreateRequest(uri, HttpMethods.POST, strData, "application/xml");
request.KeepAlive = false;
request.ProtocolVersion = HttpVersion.Version10;
try
{
using (var response = (HttpWebResponse)request.GetResponse())
{
return response.GetResponseStream().ToString();
}
}
catch (Exception ex)
{
MessageBox.Show("SendXMLFile exception " + ex.Message);
request.Abort();
return string.Empty;
}
}
private static string GetDataFromXMLFile()
{
// test data - if it works, get the (same, for now) data from the file
return #"<?xml version=1.0?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>"; //had to remove "s from version num
}
// Based on code from Andy Wiggly (the owner of Wiggly Field in Chicago and the Wiggly chewing gum company?)
public static HttpWebRequest CreateRequest(string uri, HttpMethods method, string data, string contentType)
{
WebRequest request = HttpWebRequest.Create(uri);
request.Method = Enum.ToObject(typeof(HttpMethods), method).ToString();
request.ContentType = contentType;
((HttpWebRequest)request).Accept = contentType;
if (method != HttpMethods.GET && method != HttpMethods.DELETE)
{
Encoding encoding = Encoding.UTF8;
request.ContentLength = encoding.GetByteCount(data);
request.ContentType = contentType;
request.GetRequestStream().Write(
encoding.GetBytes(data), 0, (int)request.ContentLength);
request.GetRequestStream().Close();
}
else
{
// If we're doing a GET or DELETE don't bother with this
request.ContentLength = 0;
}
// Finally, return the newly created request to the caller.
return request as HttpWebRequest;
}
Note: I don't know if this is just a misleading side-effect of shutting down the server, but I subsequently saw this err msg in the client/handheld app:
"System.Net.ProtocolVi..."
"This operation cannot be performed after the request has been submitted."
UPDATE 5
For those wanting a Stack Trace, &c:
serNum and siteNum are simple values that get concatenated into the uri like so:
string uri = string.Format("http://192.168.125.50:28642/api/FileTransfer/GetHHSetupUpdate?serialNum={0}&clientVersion={1}", serNum, clientVer);
I tried to get the Stack Trace like so:
catch (Exception ex)
{
MessageBox.Show(string.Format("Msg = {0}; StackTrace = {1)", ex.Message, ex.StackTrace));
request.Abort();
return string.Empty;
}
...but now I'm only seeing, "This operation cannot be performed after the request has been submitted."
UPDATE 6
I changed the method signature to this:
public static HttpWebResponse SendXMLFile(string xmlFilepath, string uri)
...and the corresponding code to this:
try
{
using (var response = (HttpWebResponse)request.GetResponse())
{
return response;
}
}
catch (Exception ex)
{
MessageBox.Show(string.Format("Msg = {0}; StackTrace = {1)", ex.Message, ex.StackTrace));
request.Abort();
return null;
}
...but it made no difference (and I see no "StackTrave = " message, so it must be failing erstwheres)
UPDATE 7
I put two debug strings in:
0)
public static HttpWebRequest CreateRequestNoCredentials(string uri, HttpMethods method, string data, string contentType)
{
//test:
MessageBox.Show(string.Format("In CreateRequestNoCredentials(); data passed in = {0}", data));
1) In SendXMLFile():
//test:
MessageBox.Show(string.Format("After calling CreateRequestNoCredentials(), request contentLen = {0}, headers = {1}, requestUri = {2}",
request.ContentLength, request.Headers, request.RequestUri));
...and I see this:
...but then before the second one gets a chance to show me the gory details, the server receives the null body value, crashes thuswith, and then the client whin[g]es with the same old "This operation cannot be performed after the request has been submitted" complaint.
UPDATE 8
In response to the suggestion, "I suspect that if you remove the setting of KeepAlive and ProtocolVersion after the CreateRequest call, the exception will go away.", I changed my code from this:
HttpWebRequest request = CreateRequestNoCredentials(uri, HttpMethods.POST, strData, "application/xml");
//test:
MessageBox.Show(string.Format("After calling CreateRequestNoCredentials(), request contentLen = {0}, headers = {1}, requestUri = {2}",
request.ContentLength, request.Headers, request.RequestUri));
request.KeepAlive = false;
request.ProtocolVersion = HttpVersion.Version10;
public static HttpWebRequest CreateRequestNoCredentials(string uri, HttpMethods method, string data, string contentType)
{
//test:
MessageBox.Show(string.Format("In CreateRequestNoCredentials(); data passed in = {0}", data));
WebRequest request = HttpWebRequest.Create(uri);
request.Method = Enum.ToObject(typeof(HttpMethods), method).ToString();
request.ContentType = contentType;
((HttpWebRequest)request).Accept = contentType;
if (method != HttpMethods.GET && method != HttpMethods.DELETE)
{
Encoding encoding = Encoding.UTF8;
request.ContentLength = encoding.GetByteCount(data);
request.ContentType = contentType;
request.GetRequestStream().Write(
encoding.GetBytes(data), 0, (int)request.ContentLength);
request.GetRequestStream().Close();
}
else
{
// If we're doing a GET or DELETE don't bother with this
request.ContentLength = 0;
}
// Finally, return the newly created request to the caller.
return request as HttpWebRequest;
}
...to this:
HttpWebRequest request = CreateRequestNoCredentials(uri, HttpMethods.POST, strData, "application/xml");
//test:
MessageBox.Show(string.Format("After calling CreateRequestNoCredentials(), request contentLen = {0}, headers = {1}, requestUri = {2}",
request.ContentLength, request.Headers, request.RequestUri));
public static HttpWebRequest CreateRequestNoCredentials(string uri, HttpMethods method, string data, string contentType)
{
//test:
MessageBox.Show(string.Format("In CreateRequestNoCredentials(); data passed in = {0}", data));
WebRequest request = HttpWebRequest.Create(uri);
request.Method = Enum.ToObject(typeof(HttpMethods), method).ToString();
request.ContentType = contentType;
((HttpWebRequest)request).Accept = contentType;
// moved from elsewhere to here:
((HttpWebRequest)request).KeepAlive = false;
((HttpWebRequest)request).ProtocolVersion = HttpVersion.Version10;
if (method != HttpMethods.GET && method != HttpMethods.DELETE)
{
Encoding encoding = Encoding.UTF8;
request.ContentLength = encoding.GetByteCount(data);
request.ContentType = contentType;
request.GetRequestStream().Write(
encoding.GetBytes(data), 0, (int)request.ContentLength);
request.GetRequestStream().Close();
}
else
{
// If we're doing a GET or DELETE don't bother with this
request.ContentLength = 0;
}
// Finally, return the newly created request to the caller.
return request as HttpWebRequest;
}
...and yet I still get that same err msg ("This operation cannot be performed after the request has been submitted") and stringifiedXML is still null when it hits the server.
UPDATE 9
Here is what I get when I send what I understand to be what I should via Fiddler 2 (right-click the image and open in a new tab if you don't have visual superpowers):
...but I don't know what I'm looking at...did it work? Did it fail? The "body == 0" column gives me pause/makes me think it failed, yet "204" seems to mean "The server successfully processed the request, but is not returning any content"...
UPDATE 10
Here is the Fiddler scream shot after fixing the uri, and I do reach the breakpoint in the server app, with good data sent:
UPDATE 11
With changing this code:
string strData = sb.ToString();
HttpWebRequest request = CreateRequestNoCredentials(uri, HttpMethods.POST, strData, "application/xml");
...to this:
string strData = #sb.ToString(); // GetDataFromXMLFile();
string body = String.Format("\"{0}\"", strData);
HttpWebRequest request = CreateRequestNoCredentials(uri, HttpMethods.POST, body, "application/json");
...I'm now getting this in stringifiedXML: "
...and so I'm now getting: "System.Xml.XmlException was unhandled by user code
HResult=-2146232000
Message=Unexpected end of file has occurred. Line 1, position 15..."
It's an improvement, anyway...
UPDATE 12
Depending on the exact makeup/formatting of the string passed as "Request Body" in Fiddle, the results differ radically.
With this as Request Body:
<?xml version="1.0"?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>
...stringifiedXML is null
With this as Request Body:
"<?xml version=1.0?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>"
...stringifiedXML is exactly the same ("")
...but there is an exception:
System.Xml.XmlException was unhandled by user code
HResult=-2146232000
Message='1.0' is an unexpected token. The expected token is '"' or '''. Line 1, position 15.
Source=System.Xml
LineNumber=1
LinePosition=15
SourceUri=""
StackTrace:
at System.Xml.XmlTextReaderImpl.Throw(Exception e)
at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
at System.Xml.XmlTextReaderImpl.ThrowUnexpectedToken(String expectedToken1, String expectedToken2)
at System.Xml.XmlTextReaderImpl.ParseXmlDeclaration(Boolean isTextDecl)
at System.Xml.XmlTextReaderImpl.Read()
at System.Xml.Linq.XDocument.Load(XmlReader reader, LoadOptions options)
at System.Xml.Linq.XDocument.Parse(String text, LoadOptions options)
at System.Xml.Linq.XDocument.Parse(String text)
at HandheldServer.Controllers.DeliveryItemsController.d__2.MoveNext() in c:\HandheldServer\HandheldServer
\Controllers\DeliveryItemsController.cs:line 63
InnerException:
With this as Request Body:
"<?xml version="1.0"?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>"
...stringifiedXML is "
Penultimately, with this as Request Body:
"<?xml version=\"1.0\"?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>"
...stringifiedXML is exactly the same thing ("")
...but I get this exception:
System.InvalidOperationException was unhandled by user code
HResult=-2146233079
Message=Sequence contains no elements
Source=System.Core
StackTrace:
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
at HandheldServer.Controllers.DeliveryItemsController.d__2.MoveNext() in c:\HandheldServer\HandheldServer\Controllers\DeliveryItemsController.cs:line 109
InnerException:
And finally, if I pass this, with (albeit bogus) vals within the angulars:
"<?xml version=\"1.0\"?><LocateAndLaunch><Tasks>Some Task</Tasks><Locations>Some Location</Locations></LocateAndLaunch>"
...I STILL get "sequence contains no elements"
This method is more picky than Rachel Canning! What does it want - egg in its beer?!?
UPDATE 13
With this code:
public async void PostArgsAndXMLFileAsStr([FromBody] string stringifiedXML, string serialNum, string siteNum)
{
XDocument doc = XDocument.Parse(await Request.Content.ReadAsStringAsync());
...or this:
. . .XDocument doc = XDocument.Load(await Request.Content.ReadAsStreamAsync());
...and this as the incoming stringifiedXML:
"Some TaskSome Location"
...I get the exception:
"System.Xml.XmlException was unhandled by user code
HResult=-2146232000
Message=Root element is missing."
With this code (same stringifiedXML):
XDocument doc = XDocument.Parse(stringifiedXML);
... I get, "System.InvalidOperationException was unhandled by user code
HResult=-2146233079
Message=Sequence contains no elements
Source=System.Core
StackTrace:
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
at HandheldServer.Controllers.DeliveryItemsController.d__2.MoveNext() in c:\HandheldServer\HandheldServer
\Controllers\DeliveryItemsController.cs:line 109
InnerException: "
IOW, depending on how I parse the incoming string, I get either "Root element is missing" or "Sequence contains no elements"
What the Deuce McAlistair MacLean Virginia Weeper?!? Isn't "<LocateAndLaunch>" a root element? Aren't "Some Task" and "Some Location" elements?
For the action method like this
public async void PostArgsAndXMLFileAsStr([FromBody] string stringifiedXML,
string serialNum, string siteNum)
{}
the request message must be like this. I use JSON here.
POST http://localhost:port/api/values/PostArgsAndXMLFileAsStr?serialNum=1&siteNum=2 HTTP/1.1
Content-Type: application/json
Host: localhost:port
Content-Length: 94
"<?xml version=1.0?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>"
The request body needs to contain the double quotes, BTW. With this, binding should work correctly.
So, post the message with content type application/json and format the body like this.
string content = #"<?xml version=1.0?><LocateAndLaunch><Tasks></Tasks><Locations></Locations></LocateAndLaunch>";
string body = String.Format("\"{0}\"", content);
Before, you change anything in the client side code, use Fiddler to send a POST like the one above to ensure it works in the web API side. After that, change your client side to make sure it outputs the request just the working request with Fiddler.
I have a rest service written to receive a file and save it.
The problem is that when I receive more than 2 requests, the files are not written only the last request is taken into consideration and written.
Here is my code:
#POST
#RequestMapping(value = "/media/{mediaName}/{mediaType}")
#Produces(MediaType.APPLICATION_OCTET_STREAM)
#ResponseBody
public String updateResourceLocally(#FormDataParam("rawData") InputStream rawData, #PathVariable("mediaName") String mediaName, #PathVariable("mediaType") String mediaType) {
logger.info("Entering updateResourceLocally for " + jobId + "; for media type: " + mediaType);
final String storeDir = "/tmp/test/" + mediaName + ("/");
final String finalExtension = mediaType;
final InputStream finalRawData = rawData;
// new Thread(new Runnable() {
// public void run() {
// writeToFile(finalRawData, storeDir, finalExtension);
// }
// }).start();
writeToFile(finalRawData, storeDir, finalExtension);
// int poolSize = 100;
// ExecutorService executor = Executors.newFixedThreadPool(poolSize);
// executor.execute(new Runnable() {
// #Override
// public void run() {
// writeToFile(rawData, storeDir, finalExtension);
// }
// });
logger.info("File uploaded to : " + storeDir);
return "Success 200";
}
I tried to put the writeToFile into threads, but still no success. Here is what writeToFile does
public synchronized void writeToFile(InputStream rawData,
String uploadedFileLocation, String extension) {
StringBuilder finalFileName = null;
String currentIncrement = "";
String fileName = "raw";
try {
File file = new File(uploadedFileLocation);
if (!file.exists()) {
file.mkdirs();
}
while (true) {
finalFileName = new StringBuilder(fileName);
if (!currentIncrement.equals("")) {
finalFileName.append("_").append(currentIncrement).append(extension);
}
File f = new File(uploadedFileLocation + finalFileName);
if (f.exists()) {
if (currentIncrement.equals("")) {
currentIncrement = "1";
} else {
currentIncrement = (Integer.parseInt(currentIncrement) + 1) + "";
}
} else {
break;
}
}
int read = 0;
byte[] bytes = new byte[1024];
OutputStream out = new FileOutputStream(new File(uploadedFileLocation + finalFileName));
while ((read = rawData.read(bytes)) != -1) {
out.write(bytes, 0, read);
}
out.flush();
out.close();
} catch (IOException e) {
throw new RuntimeException(e.getMessage());
}
}
The writeToFile creates a folder and writes a file, if the file already exists, it appends 1 and then increments the 1 accordingly and writes the file, so I would get raw.zip, raw-1.zip, etc.
I think the inputstream bytes are being lost, am I correct in my assumption?
NOTE: I do not have a UI client, I am using Poster a Firefox extension.
Update: What I am trying to achieve here is very simple
I receive number of requests with files attached
I need to save them. If the mediaName and mediaType are the same, then I need to append something to the filename and save it in the same location
If they are different I do not have a problem
The problem I am facing with the current code is that, when I post multiple time to the same URL, I have file-names created according to what I want, but the file content is not right, they vary depending on when the request came in and only the last POST's request is written properly.
Eg. I have a zip file of size 250MB, when I post 5 time, the 1st four will have random sizes and the 5th will have the complete 250MB, but the previous four should also have the same content.
You must separate the stream copy from the free filename assignation. The stream copy must be done within the calling thread (jersey service). Only the file naming operation must be common to all threads/requests.
Here is your code with a little refactoring :
getNextFilename
This file naming operation must be synchronized to guarantee each call gives a free name. This functions creates an empty file to guarantee the next call to work, because the function relies on file.exists().
public synchronized File getNextFilename(String uploadedFileLocation, String extension)
throws IOException
{
// This function MUST be synchronized to guarantee unicity of files names
// Synchronized functions must be the shortest possible to avoid threads waiting each other.
// No long job such as copying streams here !
String fileName = "raw";
//Create directories (if not already existing)
File dir = new File(uploadedFileLocation);
if (!dir.exists())
dir.mkdirs();
//Search for next free filename (raw.<extension>, else raw_<increment>.<extension>)
int currentIncrement = 0;
String finalFileName = fileName + "." + extension;
File f = new File(uploadedFileLocation + finalFileName);
while (f.exists())
{
currentIncrement++;
finalFileName = fileName + "_" + currentIncrement + "." + extension;
f = new File(uploadedFileLocation + finalFileName);
}
//Creates the file with size 0 in order to physically reserve the file "raw_<n>.extension",
//so the next call to getNextFilename will find it (f.exists) and will return "raw_<n+1>.extension"
f.createNewFile();
//The file exists, let the caller fill it...
return f;
}
writeToFile
Must not be synchronized !
public void writeToFile(InputStream rawData, String uploadedFileLocation, String extension)
throws IOException
{
//(1) Gets next available filename (creates the file with 0 size)
File file = getNextFilename(uploadedFileLocation, extension);
//(2) Copies data from inputStream to file
int read = 0;
byte[] bytes = new byte[1024];
OutputStream out = new FileOutputStream(file);
while ((read = rawData.read(bytes)) != -1) {
out.write(bytes, 0, read);
}
out.flush();
out.close();
}
i am using GWTUpload to upload a file.
i am getting the server info, file name, content type etc.. in onFinishHandler, but there's no option to get the file content from server to client.
Note : am trying to upload XML File and EXCEL File
i am using GWT 2.4, GXT 3.0.1, GWTUpload 0.6.6
here's the sample code
Client Code - OnFinishHandler
u.addOnFinishUploadHandler(new OnFinishUploaderHandler() {
#Override
public void onFinish(IUploader uploader) {
if (uploader.getStatus() == Status.SUCCESS) {
System.err.println(uploader.getServerResponse());
UploadedInfo info = uploader.getServerInfo();
System.out.println("File name " + info.name);
System.out.println("File content-type " + info.ctype);
System.out.println("File size " + info.size);
System.out.println("Server message " + info.message);
}
}
});
Servlet Code
public class GWTFileUploadServlet extends UploadAction {
private static final long serialVersionUID = -6742854283091447922L;
String fileContent;
File uploadedFile;
#Override
public String executeAction(HttpServletRequest request,
List<FileItem> sessionFiles) throws UploadActionException {
String response = "";
int cont = 0;
for (FileItem item : sessionFiles) {
if (false == item.isFormField()) {
cont++;
try {
File file = File.createTempFile("upload-", ".bin");
item.write(file);
uploadedFile = file;
fileContent = item.getContentType();
response += "File saved as " + file.getAbsolutePath();
} catch (Exception e) {
throw new UploadActionException(e.getMessage());
}
}
}
removeSessionFileItems(request);
return response;
}
#Override
public void getUploadedFile(HttpServletRequest request,
HttpServletResponse response) throws IOException {
if (fileContent != null && !fileContent.isEmpty()) {
response.setContentType(fileContent);
FileInputStream is = new FileInputStream(uploadedFile);
copyFromInputStreamToOutputStream(is, response.getOutputStream());
} else {
renderXmlResponse(request, response, XML_ERROR_ITEM_NOT_FOUND);
}
}
}
please help me....
You can read the file you have created in the filesystem when you called item.write(...), but it is better if you get an InputStream from the FileItem you received and write its content anywhere. For instance if the content is a String you can use a StringWritter to get it:
InputStream inputStream = item.getInputStream();
StringWriter writer = new StringWriter();
IOUtils.copy(inputStream, writer);
String theContentString = writer.toString();
[EDITED]
To get the content of the file in client side, so you have to retrieve it from the server using any method:
As as a customized message in your gwtupload servlet if the content of the file is ascii: use return String of executeAction.
Do a RequestBuilder call to the servlet to get the file using the uploader url value.
Use any GWT ajax mechanism like RPC.
In modern browsers you can get the content of a file in client side without sending it to server side. Take a look to lib-gwt-file
In your code You can just use
byte[] file ;
file = item.get();
And You will get all the file content in an encoded format in the "file" variable .
I want to download a file from internet and I have url of that file . so I wrote a download servlet :
public class DownloadServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException {
String pathToDownload = request.getParameter("url");
URL url = new URL(pathToDownload);
URLConnection uc = url.openConnection();
String contentType = uc.getContentType();
int contentLength = uc.getContentLength();
InputStream is = uc.getInputStream();
response.setContentType(contentType);
// resp.setHeader("Content-Disposition", "attachment; filename*=\"utf-8''" + filename + "");
ServletOutputStream os = response.getOutputStream();
byte[] b = new byte[2048];
int length;
while ((length = is.read(b)) != -1) {
os.write(b, 0, length);
}
is.close();
os.close();
}
}
in this i want to show the popup when user clicks on file whether to save or not so there is
resp.setHeader("Content-Disposition", "attachment; filename*=\"utf-8''" + filename + "");
but I want the filename same as filename on internate so additionally what is needed in above snippet?
Cut substring from the last "/" to the end of the URL string - this is your file name.
String disposition = httpConn.getHeaderField("Content-Disposition");
if (disposition != null) {
// extracts file name from header field
int index = disposition.indexOf("filename=");
if (index != 0) {
fileName = disposition.substring(index + 9,
disposition.length());
}
} else {
// extracts file name from URL
fileName = link.substring(link.lastIndexOf("/") + 1,
link.length());
}
I am using GWT.
I have to download a file file from server to client.
Document is in the external repository.
Client sends the id of the document through a Servlet.
On server side: Using this ID document is retrieved:
Document document = (Document)session.getObject(docId);
ContentStream contentStream = document.getContentStream();
ByteArrayInputStream inputStream = (ByteArrayInputStream) contentStream.getStream();
int c;
while ((c = inputStream.read()) != -1) {
System.out.print((char) c);
}
String mime = contentStream.getMimeType();
String name = contentStream.getFileName();
InputStream strm = contentStream.getStream();
Here I can read the document.
I want to send this to the client.
How do I make this a file and send it back to the client?
In Your Servlet:
Document document =(Document)session.getObject(docId);
ContentStream contentStream = document.getContentStream();
String name = contentStream.getFileName();
response.setHeader("Content-Type", "application/octet-stream;");
response.setHeader("Content-Disposition", "attachment;filename=\"" + name + "\"");
OutputStream os = response.getOutputStream();
InputStream is =
(ByteArrayInputStream) contentStream.getStream();
BufferedInputStream buf = new BufferedInputStream(is);
int readBytes=0;
while((readBytes=buf.read())!=-1) {
os.write(readBytes);
}
os.flush();
os.close();// *important*
return;
You can create a standard servlet (which extends HttpServlet and not RemoteServiceServlet) on server side and opportunity to submit the id as servlet parameter on client side.
Now you need after getting request create the excel file and send it to the client. Browser shows automatically popup with download dialog box.
But you should make sure that you set the right content-type response headers. This header will instruct the browser which type of file is it.
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String fileId = reguest.getParameter("fileId"); // value of file id from request
File file = CreatorExel.getFile(fileId); // your method to create file from helper class
// setting response headers
response.setHeader("Content-Type", getServletContext().getMimeType(file.getName()));
response.setHeader("Content-Length", file.length());
response.setHeader("Content-Disposition", "inline; filename=\"" + file.getName() + "\"");
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
InputStream inputStream = new FileInputStream(file);
ServletOutputStream outputStream = response.getOutputStream();
input = new BufferedInputStream(fileInput);
output = new BufferedOutputStream(outputStream);
int count;
byte[] buffer = new byte[8192]; // buffer size is 512*16
while ((count = input.read(buffer)) > 0) {
output.write(buffer, 0, count);
}
} finally {
if (output != null) {
try {
output.close();
} catch (IOException ex) {
}
}
if (input != null) {
try {
input.close();
} catch (IOException ex) {
}
}
}