Code that download empty file and supposed not to - java

I have this part of function where it supposed to download file like pdf from server and store in new directory. It does do this but an empty pdf or text file.How to fix it.
`File urlfile = new File(host + "/" + path);
urlfile.getParentFile().mkdirs();
// create outputstream for request and inputstream for data
// download
FileOutputStream outS = new FileOutputStream(urlfile);
DataInputStream instream = new DataInputStream(newsocket.getInputStream());
// get rid of head part to get to actual file
String l = null;
String lastmodtime = null;
boolean done = false;
while (!(l = DAA.readLine()).equals("")) {
if (!done && l.contains("Last-Modified:")) {
lastmodtime = l.substring(l.indexOf(' ') + 1, l.length());
done = true;
System.out.println(l);
}
}
// read in bytes to correct file name
try {
byte[] inbytes = new byte[16384];
int input;
while ((input = instream.read(inbytes)) != -1) {
outS.write(inbytes, 0, input);
}
}`

You can try this simple code if you want to create a copy of the file or you can even use apache commons io (FileUtils.copyFile(source, dest)) for java copy file operation.
private static void copyFileUsingStream(File source, File dest)
throws IOException {
InputStream is = null;
OutputStream os = null;
try {
is = new FileInputStream(source);
os = new FileOutputStream(dest);
byte[] buffer = new byte[1024];
int length;
while ((length = is.read(buffer)) > 0) {
os.write(buffer, 0, length);
}
} finally {
is.close();
os.close();
}
}

Related

Error when i am trying to create a zip from 2 files

I am trying to combine 2 files in one zip file
myMainMethod
private void downloadFileByTypeInner(StaticDocument file, String productCode, int productVersion) throws IOException, TechnicalException {
ExternalContext ec = FacesContext.getCurrentInstance().getExternalContext();
HttpServletResponse response = (HttpServletResponse) ec.getResponse();
String distrib = MultinetFrontHelper.getDefaultDitrib();
String realPath = findRealPath(ec, file.getPath().replace("{DISTRIB}", distrib));
String downloadName = file.getDownloadFileName() != null ? file.getDownloadFileName() : file.getPath();
if (file.getAction() == null || file.getAction().trim().isEmpty() || file.getAction().equals("download")) {
List<java.io.File> l = new ArrayList<>();
java.io.File f = new java.io.File(realPath);
l.add(f);
if(file.getDependOnCodeFiles() != null){
String[] paths = file.getDependOnCodeFiles().split(",");
for (String codefile : paths) {
StaticDocument file2 = libraryBusinessService.getFileByCodeType(codefile, productCode, productVersion);
if((file2 != null)) {
l.add(new java.io.File(findRealPath(ec, file2.getPath())));
}
}
downloadName = downloadName.substring(0,downloadName.lastIndexOf("."))+".zip";
}
InputStream pathStream = DownLoadHelper.getStreamAllFiles(l.toArray(new java.io.File[0]), downloadName);
if (pathStream != null) {
if(downloadName.indexOf('/')!=-1) {
downloadName = downloadName.substring(downloadName.lastIndexOf('/')+1);
}
DownLoadHelper.downLoadFile(response, pathStream, downloadName);
} else {
logger.error("Le fichier " + realPath + " est introuvable!");
throw new TechnicalException(CodeError.CODE_ERTEMO0001, null);
}
} else if (file.getAction().equals("open")) {
final FacesContext ctx = FacesContext.getCurrentInstance();
final ExternalContext extContext = ctx.getExternalContext();
try {
extContext.redirect(file.getPath());
} catch (final IOException ioe) {
throw new FacesException(ioe);
}
}
}
getStreamAllFiles
public static InputStream getStreamAllFiles(final File[] listDoc, String nameZIP) throws IOException {
InputStream stream = null;
if (listDoc != null) {
if (listDoc.length == 1) {
stream = new ByteArrayInputStream(FileUtils.readFileToByteArray(listDoc[0]));
} else if (listDoc.length > 1) {
try( ByteArrayOutputStream baos = new ByteArrayOutputStream();ZipOutputStream zos = new ZipOutputStream(baos)){
for (int i = 0; i < listDoc.length; i++) {
try(InputStream fis = new ByteArrayInputStream(FileUtils.readFileToByteArray(listDoc[i]));BufferedInputStream bis = new BufferedInputStream(fis)){
zos.putNextEntry(new ZipEntry(listDoc[i].getName()));
byte[] bytes = new byte[1024];
int bytesRead;
while ((bytesRead = bis.read(bytes)) != -1) {
zos.write(bytes, 0, bytesRead);
}
}
}
zos.closeEntry();
stream = new ByteArrayInputStream(baos.toByteArray());
}
}
}
return stream;
}
downLoadFile
public static void downLoadFile(HttpServletResponse response,InputStream pathStream,String fileName) throws IOException {
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition",
"attachment;filename=" + fileName);
ServletOutputStream out = response.getOutputStream();
IOUtils.copyLarge(pathStream, out);
out.flush();
FacesContext.getCurrentInstance().responseComplete();
IOUtils.closeQuietly(pathStream);
IOUtils.closeQuietly(out);
}
I have this error when trying to open the zip file
I presume you're trying to make a zip file with multiple files. The issues are in your getStreamAllFiles method as you don't close the zip entry after putting the content of the file, and you don't close the ZipOutputStream and the end of the loop, so the file loop should look like:
for (int i = 0; i < listDoc.length; i++) {
try(InputStream fis = new ByteArrayInputStream(FileUtils.readFileToByteArray(listDoc[i]));BufferedInputStream bis = new BufferedInputStream(fis)){
zos.putNextEntry(new ZipEntry(listDoc[i].getName()));
byte[] bytes = new byte[1024];
int bytesRead;
while ((bytesRead = bis.read(bytes)) != -1) {
zos.write(bytes, 0, bytesRead);
}
zos.closeEntry();
}
}
zos.close();
stream = new ByteArrayInputStream(baos.toByteArray());
i.e. move the zos.closeEntry() inside the loop through the files.
Without moving it inside the listDoc.length loop, if you have more than one file you will not be closing the ZipEntry properly at the end of each entry. You also need to issue a close() on the ZipOutputStream, as otherwise it will not write the end-of-zip directory (which is shown as an error End-of-central-directory signature not found if you test the file under a command line tool.
In addition, I'd move the allocation of the byte buffer outside the file loop as you only need to allocate it once, and reuse the same buffer for all the files you're writing.

FileOutputStream creates file even if i check file existance

I'm making simple Client-Server application to make file copies on server.
There is clientside method for sending file to server:
private void makeCopy(Socket clientSock) throws IOException {
File file = new File("D:\\client\\toCopy.bmp");
File dest = new File("D:\\server\\copyFile.bmp");
boolean ifExists = dest.exists();
if(ifExists && !file.isDirectory()){
System.out.println("Copy is already made on server.");
}
else{
fis = new FileInputStream(file);
byte[] buffer = new byte[4096];
while (fis.read(buffer) > 0) {
oos.write(buffer);
}
//fis.close();
oos.close();
}
}
Also there is serverside method for receiving file from client:
public void saveFile(Socket s) throws IOException{
File copy = new File("D:\\server\\fileCopy.bmp");
fos = new FileOutputStream(copy);
File fromServer = new File("D:\\client\\toCopy.bmp");
if(copy.exists() && !copy.isDirectory()){
}
else{
byte[] buffer = new byte[4096];
int filesize = (int)fromServer.length();
int read = 0;
int totalRead = 0;
int remaining = filesize;
while((read = ois.read(buffer, 0, Math.min(buffer.length, remaining))) > 0) {
totalRead += read;
remaining -= read;
System.out.println("read " + totalRead + " bytes.");
fos.write(buffer, 0, read);
}
}
}
The problem is, even if i check file existance it still makes file which I can't open (it has 0 bytes written). Any ideas ?
FileOutputStream creates a file output stream and a file in a file system.
First you should check existence and then create FileOutputStream.
File copy = new File("D:\\server\\fileCopy.bmp");
if(copy.exists() && !copy.isDirectory()){ }
fos = new FileOutputStream(copy);
File fromServer = new File("D:\\client\\toCopy.bmp");

Reading JPEG Stream over socket gives Null characters

I am reading a .jpg file over InputStream using this code but I am receiving NULNUL...n stream after some text. Ii am reading this file link to file and link of file that I received , link is Written File link.
while ((ret = input.read(imageCharArray)) != -1) {
packet.append(new String(imageCharArray, 0, ret));
totRead += ret;
imageCharArray = new char[4096];
}
file = new File(
Environment.getExternalStorageDirectory()
+ "/FileName_/"
+ m_httpParser.filename + ".jpg");
PrintWriter printWriter = new PrintWriter(file);
// outputStream = new FileOutputStream(file); //also Used FileoutputStream for writting
// outputStream.write(packet.toString().getBytes());//
// ,
printWriter.write(packet.toString());
// outputStream.close();
printWriter.close();
}
I have also tried FileoutputStream but hardlucj for this too as commented in my code.
Edit
I have used this also. I have a content length field upto which i am reading and writing
byte[] bytes = new byte[1024];
int totalReadLength = 0;
// read untill we have bytes
while ((read = inputStream.read(bytes)) != -1
&& contentLength >= (totalReadLength)) {
outputStream.write(bytes, 0, read);
totalReadLength += read;
System.out.println(" read size ======= "
+ read + " totalReadLength = "
+ totalReadLength);
}
String is not a container for binary data, and PrintWriter isn't a way to write it. Get rid of all, all, the conversions between bytes and String and vice versa, and just transfer the bytes with input and output streams:
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
If you need to constrain the number of bytes read from the input, you have to do that before calling read(), and you also have to constrain the read() correctly:
while (total < length && (count = in.read(buffer, 0, length-total > buffer.length ? buffer.length: (int)(length-total))) > 0)
{
total += count;
out.write(buffer, 0, count);
}
I tested it in my Nexus4 and it's working for me. Here is the snippet of code what I tried :
public void saveImage(String urlPath)throws Exception{
String fileName = "kumar.jpg";
File folder = new File("/sdcard/MyImages/");
// have the object build the directory structure, if needed.
folder.mkdirs();
final File output = new File(folder,
fileName);
if (output.exists()) {
output.delete();
}
InputStream stream = null;
FileOutputStream fos = null;
try {
URL url = new URL(urlPath);
stream = url.openConnection().getInputStream();
// InputStreamReader reader = new InputStreamReader(stream);
DataInputStream dis = new DataInputStream(url.openConnection().getInputStream());
byte[] fileData = new byte[url.openConnection().getContentLength()];
for (int x = 0; x < fileData.length; x++) { // fill byte array with bytes from the data input stream
fileData[x] = dis.readByte();
}
dis.close();
fos = new FileOutputStream(output.getPath());
fos.write(fileData);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (stream != null) {
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Just Call the above function in a background thread and pass your url. It'll work for sure. Let me know if it helps.
You can check below code.
destinationFile = new File(
Environment.getExternalStorageDirectory()
+ "/FileName_/"
+ m_httpParser.filename + ".jpg");
BufferedOutputStream buffer = new BufferedOutputStream(new FileOutputStream(destinationFile));
byte byt[] = new byte[1024];
int i;
for (long l = 0L; (i = input.read(byt)) != -1; l += i ) {
buffer.write(byt, 0, i);
}
buffer.close();

How to return and delete file?

I want to return file (read or load) from method and then remove this file.
public File method() {
File f = loadFile();
f.delete();
return f;
}
But when I delete a file, I delete it from disk and then exists only descriptor to non-existing file on return statement. So what is the most effective way for it.
You can't keep the File handle of deleted file, rather you can keep the data in a byte array temporarily, delete the file and then return the byte array
public byte[] method() {
File f =loadFile();
FileInputStream fis = new FileInputStream(f);
byte[] data = new byte[fis.available()];
fis.read(data);
f.delete();
return data;
}
// Edit Aproach 2
FileInputStream input = new FileInputStream(f);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] buf = new byte[1024];
int bytesRead = input.read(buf);
while (bytesRead != -1) {
baos.write(buf, 0, bytesRead);
bytesRead = input.read(buf);
}
baos.flush();
byte[] bytes = baos.toByteArray();
you can construct the file data from byte array
However, my suggestion is to use IOUtils.toByteArray(InputStream input) from Jakarta commons, why do you want re write when already in plate
Assuming you want to return the file to the browser, this is how I did it :
File pdf = new File("file.pdf");
if (pdf.exists()) {
try {
InputStream inputStream = new FileInputStream(pdf);
httpServletResponse.setContentType("application/pdf");
httpServletResponse.addHeader("content-disposition", "inline;filename=file.pdf");
copy(inputStream, httpServletResponse.getOutputStream());
inputStream.close();
pdf.delete();
} catch (Exception e) {
e.printStackTrace();
}
}
private static int copy(InputStream input, OutputStream output) throws IOException {
byte[] buffer = new byte[512];
int count = 0;
int n = 0;
while (-1 != (n = input.read(buffer))) {
output.write(buffer, 0, n);
count += n;
}
return count;
}

Joining two mp3 files into one

I have this code to read bytes to another file.
But I'm not able to concatenate two mp3 files into one.
Am I missing something?
public static void main(String[] args) {
String strFileName = ("D:/Music/Assb/Love.mp3");
BufferedOutputStream bos = null;
try
{
//create an object of FileOutputStream
FileOutputStream fos = new FileOutputStream(new File(strFileName));
//create an object of BufferedOutputStream
bos = new BufferedOutputStream(fos);
String str = "D:/Music/Assembled/Heart001.mp3"
+ "D:/Music/Assembled/Heart002.mp3";
/*
* To write byte array to file use,
* public void write(byte[] b) method of BufferedOutputStream
* class.
*/
System.out.println("Writing byte array to file");
bos.write(str.getBytes());
System.out.println("File written");
It`s suck. Mp3 file starts with headers. For correct merging you have to skip first 32 bytes. Try this.
try {
FileInputStream fistream1 = new FileInputStream(_file_name);
File f = new File(new File(_file_name).getParent()+"/final.mp3");
if(!f.exists())
{
f.createNewFile();
}
FileOutputStream sistream = new FileOutputStream((new File(_file_name)).getParent()+"/final.mp3");
int temp;
int size = 0;
temp = fistream1.read();
while( temp != -1)
{
sistream.write(temp);
temp = fistream1.read();
};
fistream1.close();
FileInputStream fistream2 = new FileInputStream(temp_file);
fistream2.read(new byte[32],0,32);
temp = fistream2.read();
while( temp != -1)
{
sistream.write(temp);
temp = fistream2.read();
};
fistream2.close();
sistream.close();
} catch (IOException e) {
e.printStackTrace();
}
You need to do this in two steps
String str = "D:/Music/Assembled/Heart001.mp3";
>>> ADD code to open the file given by str <<<<
bos.write(strFile.getBytes());
>>> Add code to close the file
str = "D:/Music/Assembled/Heart002.mp3";
>>> ADD code to open the file given by str <<<<
bos.write(strFile.getBytes());
>>> Add code to close the file
And as you can see you need code to open the mp3 file to read it
What Are You Trying For...Actually..if You Want To Read 2 Files to Byte Stream the dont String str = "D:/Music/Assembled/Heart001.mp3"
+ "D:/Music/Assembled/Heart002.mp3";
make str1=D:/Music/Assembled/Heart001.mp3 and str2=D:/Music/Assembled/Heart002.mp3 and read str1,str2 seperately through bufferedoutputsream
This code will work well and merge audio of similar type with in seconds...
try {
InputStream in = new FileInputStream("C:\\a.mp3");//firstmp3
byte[] buffer = new byte[1 << 20]; // loads 1 MB of the file
OutputStream os = new FileOutputStream(new File("C:\\output.mp3", true);//output mp3
int count;
while ((count = in.read(buffer)) != -1) {
os.write(buffer, 0, count);
os.flush();
}
in.close();
in = new FileInputStream("C:\\b.mp3");//second mp3
while ((count = in.read(buffer)) != -1) {
os.write(buffer, 0, count);
os.flush();
}
in.close();
os.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

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