I have Client Server program, Client make a connection to server with its URL and server Reads a file and writes to outputstream and client will get that file and save it in a directory. Problem is I am not getting the filename I am sending in response from Server. Here is my Client Server Code.
Client,
private void receiveFile() throws IOException {
String url11="http://localhost:8080/TestServer/TestServer";
// creates a HTTP connection
URL url = new URL(UPLOAD_URL);
HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
httpConn.setUseCaches(false);
httpConn.setDoOutput(true);
httpConn.setRequestMethod("POST");
int responseCode = httpConn.getResponseCode();
String ff=httpConn.getHeaderField("filename");
System.out.println("FHeader :"+ff);
File saveFile = new File(SAVE_DIR + ff);
StringBuilder builder = new StringBuilder();
builder.append(httpConn.getResponseCode())
.append(" ")
.append(httpConn.getResponseMessage())
.append("\n");
if (responseCode == HttpURLConnection.HTTP_OK) {
// reads server's response
System.out.println(builder);
InputStream inputStream = httpConn.getInputStream();
// opens an output stream for writing file
FileOutputStream outputStream = new FileOutputStream(saveFile);
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = -1;
System.out.println("Receiving data...");
while ((bytesRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bytesRead);
}
System.out.println("Data received.");
outputStream.close();
inputStream.close();
} else {
System.out.println("Server returned non-OK code: " + responseCode);
}
}
Server ,
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int BUFF_SIZE = 1024;
byte[] buffer = new byte[BUFF_SIZE];
String filePath = "E:\\Docs\\Next stop is Kurki.MP3";
File fileMp3 = new File(filePath);
if(fileMp3.exists()){
System.out.println("FOUND : ");
} else {
System.out.println("FNF");
}
String fNmae=fileMp3.getName();
FileInputStream fis = new FileInputStream(fileMp3);
response.setContentType("audio/mpeg");
response.setHeader("Content-Disposition", "attachment; filename=\"" + fNmae + "\"");
response.addHeader("fName", fNmae);
response.setContentLength((int) fileMp3.length());
OutputStream os = response.getOutputStream();
try {
int byteRead = 0;
while ((byteRead = fis.read(buffer)) != -1) {
os.write(buffer, 0, byteRead);
}
os.flush();
} catch (Exception excp) {
// downloadComplete = "-1";
excp.printStackTrace();
} finally {
os.close();
fis.close();
}
}
I feel everything is correct in Server side , Can any one help me to sort this. It would be great help . thank you.
Try this in server:
File file = new File("E:\\Docs\\Next stop is Kurki.MP3");
ResponseBuilder response = Response.ok((Object) file);
response.header("Content-Disposition",
"attachment; filename="Next stop is Kurki.MP3");
return response.build();
When client is android :
wv = webView;
wv.setDownloadListener(new DownloadListener() {
public void onDownloadStart(String url, String userAgent,
String contentDisposition, String mimetype,
long contentLength) {
String fileName = URLUtil.guessFileName(url, contentDisposition, mimetype);
DownloadManager.Request request = new DownloadManager.Request(
Uri.parse(url));
request.allowScanningByMediaScanner();
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
request.setDestinationInExternalPublicDir("/YouPath", fileName);
DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
dm.enqueue(request);
}
});
Attention here in client String fileName = URLUtil.guessFileName(url, contentDisposition, mimetype)
Related
I have express js server as API. I need to send POST request to that server and my website needs to download PDF file to the client computer.
Here is my express server code:
const pdf = await generatePDF(data.originURL, data.url, data.pageOrientation); //pdf generation
// send pdf to client
res.writeHead(200, {
'Content-Type': 'application/pdf',
'Content-Disposition': 'attachment; filename=file.pdf',
'Content-Length': pdf.length
});
res.end(pdf);
In my website I have commandButton which call the action for POST request;
What I'm a doing wrong, I'm not getting any downloaded file in my website?
Method for making POST request:
public void makeRequest() {
HttpURLConnection connection = null;
try {
String imageExportServer = "url....";
URL url = new URL(imageExportServer);
connection = (HttpURLConnection)url.openConnection();
Stopwatch stopwatch = Stopwatch.createStarted();
try {
connection.setDoOutput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/json");
try (OutputStream stream = connection.getOutputStream()) {
JsonObject configJson = new JsonObject();
configJson.addProperty("originURL", "url");
configJson.addProperty("url", "url...");
configJson.addProperty("pageOrientation", "someText");
stream.write(Builder().create().toJson(configJson).getBytes());
}
int responseCode = connection.getResponseCode();
if (responseCode != 200) {
//log.warn("Error response: ", responseCode);
}
String fileName = "";
String disposition = connection.getHeaderField("Content-Disposition");
String contentType = connection.getContentType();
int contentLength = connection.getContentLength();
System.out.println("Content-Type = " + contentType);
System.out.println("Content-Disposition = " + disposition);
System.out.println("Content-Length = " + contentLength);
System.out.println("fileName = " + fileName);
// opens input stream from the HTTP connection
InputStream inputStream = connection.getInputStream();
// opens an output stream to save into file
FileOutputStream outputStream = new FileOutputStream("neki.pdf");
int bytesRead = -1;
byte[] buffer = new byte[contentLength];
while ((bytesRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bytesRead);
}
outputStream.close();
inputStream.close();
FileOutputStream fos = new FileOutputStream("neki.pdf");
fos.write(buffer);
fos.close();
System.out.println("File downloaded");
}
} catch (IOException e) {
//log.warn(e.getMessage(), e);
} finally {
//log.info("Exporting chart of type '%s' took %sms.", "tyoe", stopwatch.elapsed(TimeUnit.MILLISECONDS));
}
} catch (IOException e) {
//log.warn(e.getMessage(), e);
} finally {
if (connection != null) {
try {
connection.disconnect();
} catch (Exception e) {
//log.warn(e.getMessage(), e);
}
}
}
}
I am using GWT to do file upload, question, how to just overwrite existing file if exists rather create a new file, ex, file(1).doc. Here is my server side code.
protected void service(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
try {
String modelPath = AutoConstants.PREFIX + "/var/models/";
File file = new File(modelPath + "/" + MODEL_NAME);
if (file.exists()) {
ServletOutputStream out = response.getOutputStream();
DataInputStream in = new DataInputStream(new FileInputStream(
file));
response.setHeader("Pragma", "public");
response.setHeader("Cache-Control",
"must-revalidate, post-check=0, pre-check=0");
response.setHeader("Content-Length",
String.valueOf(file.length()));
response.setHeader("Content-Disposition",
"attachment; fileName=\"" + MODEL_NAME + "\"");
int i = 0;
int BUFSIZE = 8192;
byte[] bbuf = new byte[BUFSIZE];
while ((in != null) && ((i = in.read(bbuf)) != -1)) {
out.write(bbuf, 0, i);
}
in.close();
out.flush();
}
} catch (Exception e) {
logger.error("Exception.getModel", e);
throw new ServletException(e.getMessage());
}
}
I am trying to create a endpoint to render/serve PDF file.
I have gone through the following links to build the API, but still facing some issues.
link 1
link 2
Following is my code :
byte[] targetArray = null;
InputStream is = null;
InputStream objectData = object.getObjectContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(objectData));
char[] charArray = new char[8 * 1024];
StringBuilder builder = new StringBuilder();
int numCharsRead;
while ((numCharsRead = reader.read(charArray, 0, charArray.length)) != -1) {
builder.append(charArray, 0, numCharsRead);
}
reader.close();
objectData.close();
object.close();
targetArray = builder.toString().getBytes();
is = new ByteArrayInputStream(targetArray);
return ResponseEntity.ok().contentLength(targetArray.length).contentType(MediaType.APPLICATION_PDF)
.cacheControl(CacheControl.noCache()).header("Content-Disposition", "attachment; filename=" + "testing.pdf")
.body(new InputStreamResource(is));
When I hit my API using postman, I am able to download PDF file but the problem is it is totally blank. What might be the issue ?
There are multiple ways to download files from server, you can use ResponseEntity<InputStreamResource>, HttpServletResponse.Below are the two methods to download.
#GetMapping("/download1")
public ResponseEntity<InputStreamResource> downloadFile1() throws IOException {
File file = new File(FILE_PATH);
InputStreamResource resource = new InputStreamResource(new FileInputStream(file));
return ResponseEntity.ok()
.header(HttpHeaders.CONTENT_DISPOSITION,
"attachment;filename=" + file.getName())
.contentType(MediaType.APPLICATION_PDF).contentLength(file.length())
.body(resource);
}
OR
You can use StreamingResponseBody to download large files. In this case server writes data to OutputStream at same time Browser read data which means its parallel.
#RequestMapping(value = "downloadFile", method = RequestMethod.GET)
public StreamingResponseBody getSteamingFile(HttpServletResponse response) throws IOException {
response.setContentType("application/pdf");
response.setHeader("Content-Disposition", "attachment; filename=\"demo.pdf\"");
InputStream inputStream = new FileInputStream(new File("C:\\demo-file.pdf"));
return outputStream -> {
int nRead;
byte[] data = new byte[1024];
while ((nRead = inputStream.read(data, 0, data.length)) != -1) {
System.out.println("Writing some bytes..");
outputStream.write(data, 0, nRead);
}
};
}
You can try to use apache commons IOUtils. Why reinvent wheel :)
1. Open a connection to remote server
2. Copy the inputStream to the destination file outputStream.
public void downloadFileFromRemoteLocation(String serverlocation, File destinationFile) throws IOException
{
try (FileOutputStream fos = new FileOutputStream( destinationFile )){
URL url = new URL(serverlocation);
URLConnection connection = url.openConnection();
IOUtils.copy( connection.getInputStream(), fos);
}
}
if you want to stick to just Java then look at snippet below
try {
// Get the directory and iterate them to get file by file...
File file = new File(fileName);
if (!file.exists()) {
context.addMessage(new ErrorMessage("msg.file.notdownloaded"));
context.setForwardName("failure");
} else {
response.setContentType("APPLICATION/DOWNLOAD");
response.setHeader("Content-Disposition", "attachment"+
"filename=" + file.getName());
stream = new FileInputStream(file);
response.setContentLength(stream.available());
OutputStream os = response.getOutputStream();
os.close();
response.flushBuffer();
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (stream != null) {
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
I take a picture using the android.hardware.Camera API. I then convert it to a Bitmap of half the actual size, compress it to a JPEG of quality 80, convert it to Base64 and send it to the server as follows.
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 80, byteArrayOutputStream);
byte[] byteArray = byteArrayOutputStream.toByteArray();
String encoded = Base64.encodeToString(byteArray, Base64.NO_WRAP);
String json_response = "";
try {
URL url = new URL("https://example.com/api_endpoint");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(15000);
conn.setConnectTimeout(15000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write("?reg=" + regCode);
writer.write("&img=" + encoded);
writer.flush();
writer.close();
os.close();
Log.d("Auth", conn.getResponseCode() + "");
InputStreamReader in = new InputStreamReader(conn.getInputStream());
BufferedReader br = new BufferedReader(in);
String text = "";
while ((text = br.readLine()) != null) {
json_response += text;
}
conn.disconnect();
} catch (IOException e) {
Log.d(getClass().getName(), "" + e.getMessage());
}
This works as expected. Now, If I don't resize the image and keep the quality 100%, how should I go about to avoid an OutOfMemoryError? My application requires the image to be in the full resolution and best quality possible.
My questions are:
Is the way I am uploading the correct way?
How to send Image is best quality without OutOfMemoryError i.e. how to optimize RAM usage in this process?
Here is my image/file uploader class:
public class ImageUploader extends AsyncTask<String, String, String> {
File imageFile = null;
String fileName = null;
public ImageUploader(File imageFile, String fileName){
this.imageFile = imageFile;
this.fileName = fileName;
}
#Override
protected String doInBackground(String... params) {
String url_str = params[0];
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
String Tag="fSnd";
try {
URL url = new URL(url_str);
HttpURLConnection c = (HttpURLConnection) url.openConnection();
c.setRequestMethod("POST");
c.setDoInput(true);
c.setDoOutput(true);
c.setRequestProperty("Connection", "Keep-Alive");
c.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
c.connect();
DataOutputStream dos = new DataOutputStream(c.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos.writeBytes("Content-Disposition: form-data; name=\"file\";filename=\"" + this.fileName + "\"" + lineEnd);
dos.writeBytes(lineEnd);
FileInputStream fin = new FileInputStream(imageFile);
int bytesAvailable = fin.available();
int maxBufferSize = 1024;
int bufferSize = Math.min(bytesAvailable, maxBufferSize);
byte[ ] buffer = new byte[bufferSize];
int bytesRead = fin.read(buffer, 0, bufferSize);
while (bytesRead > 0)
{
dos.write(buffer, 0, bufferSize);
bytesAvailable = fin.available();
bufferSize = Math.min(bytesAvailable,maxBufferSize);
bytesRead = fin.read(buffer, 0,bufferSize);
}
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
fin.close();
dos.flush();
dos.close();
StringBuilder response = new StringBuilder();
BufferedReader reader = new BufferedReader(new InputStreamReader(c.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
response.append(line);
}
return response.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
}
return null;
}
}
Usage:
new ImageUploader(pictureFile, "sample.jpg"){
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
Toast.makeText(getApplicationContext(), s, Toast.LENGTH_LONG).show();
}
}.execute("http://example/upload.php");
PHP:
<?php
$file = explode('.', $_FILES['file']['name']);
$ext = $file[count($file) - 1];
$name = substr($_FILES['file']['name'], 0, (strlen($ext) + 1) * -1);
$location = 'images/';
$cntr = 1;
$tmp_name = $name;
if(move_uploaded_file($_FILES['file']['tmp_name'], $location.$tmp_name.'.'.$ext)){
echo "Image was uploaded.";
}else{
echo "Image was not uploaded.";
}
?>
If you have the control over the API endpoint. Then try to implement the POST request to accept multi-part uploading from client side.
On client-side, have something like this to upload the image to API (with Okhttp client)
private static final String IMGUR_CLIENT_ID = "...";
private static final MediaType MEDIA_TYPE_PNG = MediaType.parse("image/png");
private final OkHttpClient client = new OkHttpClient();
public void run() throws Exception {
// Use the imgur image upload API as documented at https://api.imgur.com/endpoints/image
RequestBody requestBody = new MultipartBody.Builder()
.setType(MultipartBody.FORM)
.addFormDataPart("title", "Square Logo")
.addFormDataPart("image", "logo-square.png",
RequestBody.create(MEDIA_TYPE_PNG, new File("website/static/logo-square.png")))
.build();
Request request = new Request.Builder()
.header("Authorization", "Client-ID " + IMGUR_CLIENT_ID)
.url("https://api.imgur.com/3/image")
.post(requestBody)
.build();
Response response = client.newCall(request).execute();
if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);
System.out.println(response.body().string());
}
I think problem not with downloading to server. If I understand correctly, you getting image from camera and sending it. Note, that if you using simple request intent, that returns in onActivityResult() - Bitmap Image - this may be point of OutOfMemoryException...
Solution it's use another form on Intent() method, (that can get storage path in his parameters) for getting photo from camera, that doesn't return Bitmap image. But save photo to path, which you specified. And now you can do anything with photo in path, without OutOfMemoryException...
Sample starting correct Intent:
File destination = new File(Environment.getExternalStorageDirectory(),
"image.jpg");
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT,
Uri.fromFile(destination));
startActivityForResult(intent, CAMERA_PICTURE);
Let me know, this helps...
My download scenario is: when i click on download link on jsp it calls signed applet method with file's id, from applet I call server side method by passing that id. I can get that file at server side but I want to return/pass that file back to my applet function.
My question is how to return back or pass downloaded file to my applet?
Or How can I set a file to response object at server side that can be useful at applet?
My Signed Applet :
private static void downloadEncryptedFile(String uuid) throws HttpException, IOException {
String uri = "http://localhost:8080/encryptFileDownload.works?uuid="+uuid;
HttpClient client = new HttpClient();
PostMethod postMethod = new PostMethod(uri);
postMethod.setRequestHeader("Content-type", "text/xml; charset=ISO-8859-1");
client.executeMethod(postMethod);
postMethod.releaseConnection();
}
My Server side function:
#RequestMapping(value = "/encryptFileDownload/{uuid}.works", method = RequestMethod.POST)
public String downloadEncryptFile(#PathVariable("uuid") String uuid, HttpSession session, HttpServletResponse response) {
try {
if (StringUtils.isNotEmpty(uuid)) {
LOG.info("-----UUID----");
Node node = contentRetrieveService.getByNodeId(uuid);
Node resource = node.getNode("jcr:content");
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", "attachment; filename=\"" + node.getName() + "\"");
InputStream in = resource.getProperty("jcr:data").getBinary().getStream();
ServletOutputStream outs = response.getOutputStream();
int i = 0;
while ((i = in.read()) != -1) {
outs.write(i);
}
outs.flush();
outs.close();
in.close();
LOG.info("File Downloaded");
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
I got the solution; I just wanted to pass a file id download it and return that file back to my applet, hence I have made changes in my code as:
My Applet:
try {
URL urlServlet = new URL("uri for your servlet");
URLConnection con = urlServlet.openConnection();
con.setDoInput(true);
con.setDoOutput(true);
con.setUseCaches(false);
con.setRequestProperty(
"Content-Type",
"application/x-java-serialized-object");
// send data to the servlet
OutputStream outstream = con.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(outstream);
oos.writeObject(uuid);
oos.flush();
oos.close();
// receive result from servlet
InputStream instr = con.getInputStream();
ObjectInputStream inputFromServlet = new ObjectInputStream(instr);
String name = con.getHeaderField("filename");
File fi = new File(name);
int i = 0;
while ((i = inputFromServlet.read()) != -1) {
System.out.println(inputFromServlet.readLine());
}
inputFromServlet.close();
instr.close();
} catch (Exception ex) {
ex.printStackTrace();
}
Server side Function just replace with this:
OutputStream outs = response.getOutputStream();
outputToApplet = new ObjectOutputStream(outs);
int i = 0;
while ((i = in.read()) != -1) {
outputToApplet.write(i);
}