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Downloading file with SharePoint API: file damaged

I'm developing a Java library for basic operations on SharePoint using Graph API.
I make a call on this entry point using SOAP UI:
https://graph.microsoft.com/v1.0/drives/{drive-id}/items/{item-id}/content
And I obtain a raw response:
%PDF-1.6
%âãÏÓ
1751 0 obj
<</Filter/FlateDecode/First 98/Length 322/N 11/Type/ObjStm>>stream
hޜԽJ1†á[ÉL’ó“–m,md±ÁElTü)¼{3“wXYDØ©¾3!ç<)&I^kˆ!ymÁ¤gë¥ÍE ...
endstream
endobj
startxref
2993893
%%EOF
It look like i'm retrieving an input stream.
In the HttpRequest class I try to build a response object that returns the InputStream. My property fileInputStream is an InputStream:
SharePointDownloadResponseModel returnValue = new SharePointDownloadResponseModel();
InputStream inputStream = new ByteArrayInputStream(response.toString().getBytes(StandardCharsets.UTF_8));
returnValue.setFileInputStream(inputStream);
return returnValue;
Now in my manager class I try to save the input stream in the hard drive. I handle 2 cases. First case, I have a fileName a folder to store the file. My request object :
if(request.getDownloadFolder() != null && request.getFileName() !=null) {
InputStream initialStream = returnValue.getFileInputStream();
FileOutputStream fos = new FileOutputStream(request.getDownloadFolder() + "/" + request.getFileName());
BufferedOutputStream bos = new BufferedOutputStream(fos );
// Read bytes from URL to the local file
byte[] buffer = new byte[4096];
int bytesRead = 0;
System.out.println("Downloading " + request.getFileName());
while ((bytesRead = initialStream.read(buffer)) != -1) {
bos.write(buffer, 0, bytesRead);
}
bos.flush();
// Close destination stream
bos.close();
// Close URL stream
initialStream.close();
}
The document is created where it should be created but the file is damaged and can't be opened. I wonder what is the issue at this stage.

I finally solved my issue. Here is a basic method that shows my implementation :
public class DownloadFile {
public static void main(String[] args) throws IOException {
String url = "https://graph.microsoft.com/v1.0/drives/{driveId}/items/{itemId}/content";
SharePointCredentialRequest sharePointCredentialRequest = new SharePointCredentialRequest(Constants.TENANT_CLIENT_ID,
Constants.TENANT_CLIENT_SECRET, Constants.TENANT_AUTHORITY);
String token = Utils.getToken(sharePointCredentialRequest);
CloseableHttpClient client = HttpClients.createDefault();
HttpGet httpGet = new HttpGet(url);
httpGet.setHeader("Authorization", "Bearer " + token);
try (CloseableHttpResponse response = client.execute(httpGet)) {
HttpEntity entity = response.getEntity();
if (entity != null) {
System.out.println(response.getAllHeaders().length);
System.out.println(entity.getContentEncoding());
System.out.println(entity.getContentLength());
System.out.println(entity.getContentType().getElements().toString());
try {
// do something useful with the stream
InputStream inputStream = IOUtils.toBufferedInputStream(response.getEntity().getContent());
File targetFile = new File("C:\\myFolder\\kant.pdf");
FileUtils.copyInputStreamToFile(inputStream, targetFile);
} catch (IOException | UnsupportedOperationException e) {
e.printStackTrace();
}
}
}
}
}

File Download Java

I have written the following code to download files from the file server. While downloading, I do not get any runtime error but it always says file corrupt.
I am retrieving the file details from the database:
Reading the contents in byte form to the output stream.
This code works fine for all txt files however for all other types, the size of file increases and when i try to open, it says file is corrupted
public void download(Long requestId, HttpServletResponse response) throws Exception {
byte[] out;
ServletOutputStream outputStream;
String fileServerPath = parametersService.getParameters(AppConstants.FILE_SERVER_PATH);
FileVO fileVO = dao.getFileDetails(requestId);
String filePath = fileServerPath + fileVO.getFilePath() + fileVO.getFileName();
try {
if (FileUtil.isFileExist(filePath)) {
File apFile = new File(filePath);
InputStream in = new BufferedInputStream(new FileInputStream(apFile));
String mimeType= URLConnection.guessContentTypeFromName(apFile.getName());
if(mimeType==null){
//if mimetype is not detectable, will take default
mimeType = "application/octet-stream";
}
/* Start: Set the MIME type, file name and meta detail in response */
response.setContentType(mimeType);
response.addHeader("Content-Disposition", String.format("attachment; filename=\"%s\"", apFile.getName()));
response.addHeader("Content-Length", String.valueOf(apFile.length()));
/* End: Set the MIME type, file name and meta detail in response */
/* START: Read byte by byte and write to servlet output stream */
outputStream = response.getOutputStream();
int read;
final byte[] data = new byte[1 * 1024];
int i=0;
while ((read = in.read(data)) != -1) {
outputStream.write(data, 0, read);
i++;
slf4jLogger.debug("Writing data "+ i );
}
outputStream.flush();
in.close();
outputStream.close();
}
} catch (IOException ex) {
//Exception
}
}
My front end is in Angular 1.5. I am using file-saver lib to achieve.
Following is the code
function download() {
var url = apiHelper.getRootUrl() + '/request/' + '/download/' + vm.request.requestId;
$http.post(url, {responseType: "arraybuffer"}).success(
function (response, status, headers) {
var type = headers()['content-type'];
var disposition = headers()['content-disposition'];
if (disposition) {
var match = disposition.match(/.*filename=\"?([^;\"]+)\"?.*/);
if (match[1])
var defaultFileName = match[1];
}
defaultFileName = defaultFileName.replace(/[<>:"\/\\|?*]+/g, '_');
var blob = new Blob([response], {type: type});
saveAs(blob, defaultFileName);
});
}

Set multiple content type in handling get request

I have created a http server which handles the request and send JSON as well as exe file as response to the get request. So can we set multiple content types in one request?
Headers h = new Headers();
h = t.getResponseHeaders();
JSONObject json = new JSONObject();
json.put("version", dirFiles.lastEntry().getKey());
String output = json.toString(); // I want to send this with response
File file = new File(fileName);
h.add("CONTENT-TYPE", "application/octet-stream");
FileInputStream fs = new FileInputStream(file);
final byte[] buffer = new byte[4096];
int count = 0;
while ((count = fs.read(buffer)) >= 0) {
os.write(buffer, 0, count);
}
fs.close();
os.close();

This would require a multipart/mixed content. Each part would have a separate content type, for example application/octet-stream.

enable to Send image as Fileoutputstream via resteasy

In my server side i have an image that will be sended via rest to the client side
After sending, the image should be deleted.
So the image will be coppied on a fileoutputstream and i send the fileoutputstream to the client side and i delete the image.
i use the following code:
#GET
#Path("/get_image")
#Produces({ MediaType.APPLICATION_OCTET_STREAM })
public Response getImage(){
.......
File image = new File("myimage.png");
FileOutputStream oos = new FileOutputStream("imageToSend.png");
byte[] buf = new byte[8192];
InputStream is = new FileInputStream(image);
int c = 0;
while ((c = is.read(buf, 0, buf.length)) > 0) {
oos.write(buf, 0, c);
oos.flush();
}
ResponseBuilder response = Response.ok(oos);
response.header("Content-Disposition",
"attachment; filename=image.png");
oos.close();
is.close();
image.delete();
return response.build();
}
}
but when i execute the getImage method i found this error
org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure: Could not find MessageBodyWriter for response object of type: java.io.FileOutputStream of media type: application/octet-stream
at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:67)
at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:411)
If any one have idea about the cause of this problem....
kind regards

You should either just use the InputStream as the response body (RESTeasy will do the writing for you), or you can use StreamingOutput to write the data straight to the response stream. For example
StreamingOutput output = new StreamingOutput() {
#Override
public void write(OutputStream out) {
InputStream is = new FileInputStream(image);
int c = 0;
while ((c = is.read(buf, 0, buf.length)) > 0) {
oos.write(buf, 0, c);
oos.flush();
}
is.close();
}
}
ResponseBuilder response = Response.ok(output);
It may just be easier to use return the InputStream instead. It pretty much does the same thing under the hood, as using the StreamingOutput like above. One odd thing I've faced in the past is with large files, when trying to return InputStream. With StreamingOutput, it seemed to work better.

How to read a server file and output that as a downloadable file in users web browser in XPages

I need to read a file (that is not available on web) on the server and output it to the user as a downloadable file.
The scenario is
The user click a link from an XPage
The request is sent to the server which reads a predefined file in the server file system
The file is brought back to the user as a downloadable file in the webbrowser.
The file on the server can be in any format, e.g .pdf, .exe, .doc etc
It does not matter if this is done on SSJS or in java.
I would really appreicate some code

Here is a similar question:
How to stream file from xPages?
And here is part of the Java code taken from there and completed by me (+a fix from you!). I have now tested it also and it works:
FacesContext facesContext = FacesContext.getCurrentInstance();
XspHttpServletResponse response = (XspHttpServletResponse) facesContext.getExternalContext().getResponse();
String strFileName = "myfile.txt";
String strFilePath= "c:" + File.separator + strFileName;
response.setContentType(URLConnection.guessContentTypeFromName(strFileName));
response.setHeader("Content-Disposition","attachment;filename=" + strFileName);
//File file = new File(strFilePath);
FileInputStream fileIn = new FileInputStream(strFilePath);
ServletOutputStream out = response.getOutputStream();
int iLen = 0;
byte[] btBuffer = new byte[10240]; // Not sure about optimal buffer size
while ((iLen = fileIn.read(btBuffer)) != -1) {
out.write(btBuffer, 0, iLen);
}
facesContext.responseComplete();
out.close();
You could do all this in SSJS also.
If guessContentTypeFromName does not guess it then you need to modify the definition file on server. Or if you have a limited set of file types you can place the MIME-type table in your code/application.

Here is the code I came up with to do this, def not production code.
public static byte[] grabFile(String readFile) throws IOException {
File file = new File(readFile);
ByteArrayOutputStream ous = new ByteArrayOutputStream();
InputStream ios = new FileInputStream(file);
try {
byte []buffer = new byte[4096];
int read = 0;
while ( (read = ios.read(buffer)) != -1 ) {
ous.write(buffer, 0, read);
}
} finally {
try {
if ( ous != null )
ous.close();
} catch ( IOException e) {
}
try {
if ( ios != null )
ios.close();
} catch ( IOException e) {
}
}
return ous.toByteArray();
}
public static void download() throws IOException {
byte[] data = grabFile("\\\\server\\path\\to\\file.pdf");
HttpServletResponse response = (HttpServletResponse)FacesContext.getCurrentInstance().getExternalContext().getResponse();
response.reset();
response.setContentType("application/pdf");
response.setHeader("Content-disposition", "attachment; filename=\"filename.pdf\"");
OutputStream output = response.getOutputStream();
output.write(data);
output.close();
FacesContext.getCurrentInstance().responseComplete();
}
Then just call the download method from the beforeRenderResponse of your Xpage