Download File From Server

We could retrieve/ download the file from the server and save it locally in to the PC.

public void downLoadFileFromDevice() throws IOException

{

final FacesContext ctx = FacesContext.getCurrentInstance();

if (!ctx.getResponseComplete())

{

InputStream fileFromEvox = null;

try

{

fileFromServer = receiveFile (“serverName/filename”);

}

catch (Exception e)

{

// Error Message.

 return;

}

final String contentType = "application/x-zip-compressed";

final StringBuilder sbuff = new StringBuilder(30);

sbuff.append(“newfilefromserver.xyz”);
final HttpServletResponse response = (HttpServletResponse)ctx

 .getExternalContext().getResponse();

response.setContentType(contentType);

response.setHeader("Content-Disposition",

 "attachment;filename=\"" + sbuff.toString() + "\"");

ServletOutputStream out = null;

InputStream istream = null;

try

{

istream = new BufferedInputStream(fileFromServer);

out = response.getOutputStream();

final byte[] buf = new byte[4096];

for (int c = istream.read(buf); c != -1; c =                

istream.read(buf))

{

out.write(buf, 0, c);

}}finally{

if(istream != null)

{istream.close();}

}

 out.flush();

 ctx.responseComplete();

}}

Receive file helps to establish the connections to the server and receives the file in the InputStream format

public InputStream receiveFile(final String uri)

throws EvoxException

{

try

{

final URL serverUrl = new URL(this.evoxServer + uri);

final HttpURLConnection connection =

 (HttpURLConnection) serverUrl.openConnection();

connection.setRequestMethod(RequestType.GET.name());

connection.setDoInput(true);

connection.setDoOutput(false);

// Read the Response

return connection.getInputStream();

}

catch (IOException exception)

{

throw new Exception("unable to receive file: " + uri,

 exception);

}}