Pdf Download but not Opening decoding error - servlets

Question

This is my jsp we are calling an java method
<%
PDFFileUploader.generatePDcFile(); //Calls the PDF method;
%>
This is my PDFFileUploader code
public class PDFFileUploader {
static final String UPLOAD_URL = "http://localhost:7080/pdf/GetPDFFile";
static final int BUFFER_SIZE = 4096;
public static void generatePDcFile() throws IOException
{
System.out.println("Inside generatePDC File");
// takes file path from first program's argument
String filePath = "H:/report1.pdf";
File uploadFile = new File("H:/report1.pdf");
System.out.println("File to upload: " + filePath);
// creates a HTTP connection
URL url = new URL(UPLOAD_URL);
HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
httpConn.setUseCaches(false);
httpConn.setDoOutput(true);
httpConn.setRequestMethod("POST");
// sets file name as a HTTP header
httpConn.setRequestProperty("fileName", uploadFile.getName());
// opens output stream of the HTTP connection for writing data
OutputStream outputStream = httpConn.getOutputStream();
// Opens input stream of the file for reading data
FileInputStream inputStream = new FileInputStream(uploadFile);
byte[] buffer = new byte[BUFFER_SIZE];
int bytesRead = -1;
System.out.println("Start writing data...");
while ((bytesRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bytesRead);
}
System.out.println("Data was written.");
outputStream.close();
inputStream.close();
//Read pdc file
//FileOutputStream test = new FileOutputStream("test");
// always check HTTP response code from server
InputStream test = null;
File pdcFile = new File("H:/report123.pdf");
FileOutputStream outputStreamTest = new FileOutputStream(pdcFile);
//byte[] bufferTest = new byte[BUFFER_SIZE];
//int bytesReadTest = -1;
//final OutputStream ostream = new FileOutputStream("/tmp/data.pdc");
int responseCode = httpConn.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
// reads server's response
/* BufferedReader reader = new BufferedReader(new InputStreamReader(
httpConn.getInputStream()));*/
test = httpConn.getInputStream();
String message= httpConn.getResponseMessage();
System.out.println("Message is///"+message);
System.out.println("Header :: "+httpConn.getHeaderField(0));
final byte[] bufferTest = new byte[1024*14];
while (true) {
int len = test.read(bufferTest);
if (len <= 0) {
break;
}
outputStreamTest.write(bufferTest, 0, len);
}
outputStreamTest.close();
test.close();
String fileName = "";
String disposition = httpConn.getHeaderField("Content-Disposition");
// extracts file name from header field
int index = disposition.indexOf("filename=");
if (index > 0) {
fileName = disposition.substring(index + 10,
disposition.length() - 1);
}
System.out.println("Get File Name"+fileName);
/* Map<String, List<String>> map = httpConn.getHeaderFields();
for (Map.Entry<String, List<String>> entry : map.entrySet()) {
System.out.println("Key : " + entry.getKey() +
" ,Value : " + entry.getValue());
}*/
// String response = reader.readLine();
//System.out.println("Server's response: " + response);
} else {
System.out.println("Server returned non-OK code: " + responseCode);
}
}
from here a servlet is called through the URL provided above the code for doPost method for the getPDFFile Servlet is
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
// Gets file name for HTTP header
String fileName = request.getHeader("fileName");
File saveFile = new File(SAVE_DIR + fileName);
// prints out all header values
System.out.println("===== Begin headers =====");
Enumeration<String> names = request.getHeaderNames();
while (names.hasMoreElements()) {
String headerName = names.nextElement();
System.out.println(headerName + " = " + request.getHeader(headerName));
}
System.out.println("===== End headers =====\n");
// opens input stream of the request for reading data
InputStream inputStream = request.getInputStream();
// opens an output stream for writing file
/*FileOutputStream outputStream = new FileOutputStream(saveFile);*/
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
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();
System.out.println("File written to: " + saveFile.getAbsolutePath());
int processStatus = 0;
//temp file (used for conversion)
/* boolean success = (new File
(saveFile.getAbsolutePath())).delete();
System.out.println("File deleted :: "+success);
//delete pdc file too
boolean successtemp = (new File
(recentlyConvertedFile.getAbsolutePath())).delete();
System.out.println("File deleted :: "+successtemp);*/
response.setContentType("application/octet-stream" );
response.setHeader("Content-Disposition","inline;filename=\"" + saveFile.getName() + "\"");
response.setContentLength((int) saveFile.length());
OutputStream os = response.getOutputStream();
FileInputStream fis = new FileInputStream(saveFile);
//op.write(response.toString().getBytes(Charset.forName("utf-8")));
//op.flush();
try {
int byteRead = 0;
while ((byteRead = fis.read()) != -1) {
os.write(buffer, 0, byteRead);
}
os.flush();
} catch (Exception excp) {
excp.printStackTrace();
} finally {
os.close();
fis.close();
}
// sends response to client
//response.getWriter().print("UPLOAD DONE");
}
The file is getting downloaded but not opening the generated pdf have the same size of the original and I have taken a text file and printed the content to another file it seems to read only first line of the text file taken as input

Answer 1

Your final loop returning a file from the servlet to the client looks like this:
while ((byteRead = fis.read()) != -1) {
os.write(buffer, 0, byteRead);
}
You seem to have forgotten to use buffer in the fis.read() which should look like this:
while ((byteRead = fis.read(buffer)) != -1) {
os.write(buffer, 0, byteRead);
}
Thus, you send back as many copies of the buffer contents as fis returns numbers != -1.
BTW: Your servlet puts the data it receives into the ByteArrayOutputStream outputStream and drops that, but it claims to have written them into the file it eventually attempts to return to the caller.