Develop Reference

Faster way to Save images into internal storage

My app saves some images in internal storage when the app is loading.
The problem is that the app is using the most common code for this situation, which is compressing the image before saving it, but this compressing process takes too long to be processed. For example, if there are 5 pictures to be loaded, the app take about 30 seconds to load and open the home screen. 30 seconds is too long to open an app.
My code to save the image is the following:
public static final boolean savePngLocalStorage(String fileName, Bitmap bitmap, Context context) throws IOException {
BufferedOutputStream bos = null;
Bitmap tmp = null;
try {
bos = new BufferedOutputStream(context.openFileOutput(fileName, Context.MODE_PRIVATE)); //他アプリアクセス不可
tmp = bitmap.copy(Config.ARGB_8888, true);
return tmp.compress(Bitmap.CompressFormat.PNG, 100, bos);
} finally {
if (tmp != null) {
tmp.recycle();
tmp = null;
}
//
try {
bos.close();
} catch (Exception e) {
//IOException, NullPointerException
}
}
}
Using debug, I realized that tmp.compress command is the one that take some time to be processed.
I tried to use the following code without compressing the image. It got a bit faster.
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
ContextWrapper c = new ContextWrapper(MainActivity.this);
File path = c.getFilesDir();
String fileName = imageIdArray[i] + ".png";
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream(path + "/" + fileName); // "data/data/[package_name]/files/sample.png"
byte data[] = new byte[1024];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
total += count;
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();
Are there other ways to save the image faster?

FileOutputStream out = null;
String path = setOutputFilePath();
try {
out = new FileOutputStream(path);
croppedBitmap2.compress(Bitmap.CompressFormat.JPEG, 100, out); // bmp is your Bitmap instance
// PNG is a lossless format, the compression factor (100) is ignored
LOGGER.debug("Saving image on the absolute path folder!");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (out != null) {
out.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}

Java , Sending Large Files Over Socket is Consuming too much CPU cycles and is slow [duplicate]

This question already has answers here:
Java sending and receiving file (byte[]) over sockets
(6 answers)
Closed 7 years ago.
I was experimenting with JAVA and found this question online.
Java sending and receiving file (byte[]) over sockets.
Just for curiosity i played with the code in the accepted answer, and with other code i found similar to the question. I tried the accepted answer,yes it works and is very fast. But the problem is Archive files are getting corrupted. So here is other code i tried. The downfall of my experimental code is it consume CPU cycles and takes more time than accepted answer (And i have no idea why it is happening so). So here is my code. Can somebody help me to optimize and improve this code more.
Time Taken by accepted Answer = 11ms for 4 Mb file.
Time taken by my experiment= 4 seconds for same file.
Server.java
public class Server implements Runnable {
private ServerSocket serverSocket = null;
private Socket socket = null;
private ObjectInputStream inStream = null;
public Server() {
}
#Override
public void run() {
try {
serverSocket = new ServerSocket(4445);
socket = serverSocket.accept();
DataInputStream dIn = new DataInputStream(socket.getInputStream());
OutputStream os = socket.getOutputStream();
DataOutputStream outToClient = new DataOutputStream(os);
System.out.println("Connected");
File myFile = new File("lib1.zip");
long flength = myFile.length();
System.out.println("File Length"+flength);
outToClient.writeLong(flength);
FileInputStream fis;
BufferedInputStream bis;
byte[] mybytearray = new byte[8192];
fis = new FileInputStream(myFile);
bis = new BufferedInputStream(fis);
int theByte = 0;
System.out.println("Sending " + myFile.getAbsolutePath() + "(" + myFile.length() + " bytes)");
while ((theByte = bis.read()) != -1) {
outToClient.write(theByte);
// bos.flush();
}
/*int count;
BufferedOutputStream bos= new BufferedOutputStream(os);
while ((count = bis.read(mybytearray))>0) {
bos.write(mybytearray, 0, count);
}*/
bis.close();
socket.close();
} catch (SocketException se) {
System.exit(0);
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Thread t = new Thread(new Server());
t.start();
}
}
ReceiveFile.java
public class RecieveFile {
public final static int SOCKET_PORT = 4445; // you may change this
String SERVER = "127.0.0.1"; // localhost
ArrayList<String> logmsg = new ArrayList<>();
public static void main(String[] args) {
new RecieveFile();
}
public RecieveFile() {
try (Socket sock = new Socket(SERVER, SOCKET_PORT)) {
System.out.println("Connecting...");
try (OutputStream os = sock.getOutputStream(); DataOutputStream outToServer = new DataOutputStream(os)) {
try (DataInputStream dIn = new DataInputStream(sock.getInputStream())) {
long fileLen, downData;
int bufferSize = sock.getReceiveBufferSize();
long starttime = System.currentTimeMillis();
File myFIle = new File("lib1.zip");
try (FileOutputStream fos = new FileOutputStream(myFIle); BufferedOutputStream bos = new BufferedOutputStream(fos)) {
fileLen = dIn.readLong();
/*for (long j = 0; j <= fileLen; j++) {
int tempint = is.read();
bos.write(tempint);
}*/
downData = fileLen;
int n = 0;
byte[] buf = new byte[8192];
while (fileLen > 0 && ((n = dIn.read(buf, 0, buf.length)) != -1)) {
bos.write(buf, 0, n);
fileLen -= n;
// System.out.println("Remaining "+fileLen);
}
/*while ((n = dIn.read(buf)) > 0) {
bos.write(buf, 0, n);
}*/
bos.flush();
long endtime = System.currentTimeMillis();
System.out.println("File " + myFIle.getAbsolutePath()
+ " downloaded (" + downData + " bytes read) in " + (endtime - starttime) + " ms");
}
}
}
} catch (IOException ex) {
Logger.getLogger(RecieveFile.class.getName()).log(Level.SEVERE, null, ex);
}
}
}

You're copying a byte at a time. This is slow. You're also declaring a byte array but not using it. Try this:
int count;
byte[] buffer = new byte[8192]; // or more, double or quadruple it
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}

Your solution takes a lot of time probably because you are reading a character at time, instead of all the buffer.
The solution is to use a construct similar to the linked question; the problem you got about corrupted file is really improbable, a malformed TCP packed that pass CRC check is really rare occurrence, and I would blame a bug instead. try to post the code you used. But you can add some hash check on the file and some part of it, if you are concerned about this

Here is a cleaned up version of your code, it should perform faster as it avoids single byte operations:
public class Server implements Runnable {
#Override
public void run() {
try {
ServerSocket serverSocket = new ServerSocket(4445);
Socket socket = serverSocket.accept();
OutputStream os = socket.getOutputStream();
DataOutputStream dos = new DataOutputStream(os);
File myFile = new File("lib1.zip");
long flength = myFile.length();
dos.writeLong(flength);
InputStream fis = new FileInputStream(myFile);
byte[] buf = new byte[16*1024]; // 16K
long written = 0;
while ((count = fis.read(buf))>0) {
dos.write(buf, 0, count);
written+=count;
}
if (written != flength)
System.out.println("Warning: file changed");
dos.close();
socket.close();
} catch (IOException e) {
e.printStackTrace();
System.exit();
}
}
An possible improvement would be to use NIO with channel.sendTo() but this should already have an acceptable performance. Note you do not need to use buffered streams on reading or writing as you use a larger byte array buffer anyway.
One possible improvement would be to not use the DataOutputStream for the long but poke the 8 bytes of it into the first buffer (array) write.
BTW: writing 4MB in 11ms is 390MB/s, that would be faster than most desktop disks can read and write.

How to receive bytes from a lib to update the JProgressBar?

I've tried to receive bytes from a lib to set my JProgressBar update for a long time but unfortunately
I didn't get the result I wanted.
The problem is that I don't know how to receive bytes from a lib and how to update the JProgressBar while receiving bytes all that to make a browser with java
This is the code I've tried:
private void jTextField1KeyPressed(java.awt.event.KeyEvent evt) {
if (evt.getKeyCode() == KeyEvent.VK_ENTER){
String az = jTextField1.getText();
if(az.contains("1")){
String hh = WorkSpace.jTextField1.getText();
URLConnection conn = null;
InputStream in = null;
try {
URL url = new URL(hh);
conn = url.openConnection();
in = conn.getInputStream();
int length = conn.getContentLength();
int current = 0;
WorkSpace.jProgressBar1.setMaximum(length);
WorkSpace.jProgressBar1.setValue(0);
byte[] buffer = new byte[1024];
int numRead = 0;
while ((numRead = in.read(buffer)) != -1) {
current=0;
current += numRead;
WorkSpace.jProgressBar1.setValue(current);
}
} catch (Exception e) {
}
}
If there's someone who knows how to do this please let me know.

Just wrap the input stream in a ProgressMonitorInputStream. It will manage its own JProgressBar for you.

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 trap ftp success/failure in sun.net.ftp.FtpClient?

I want to know if really 'put' has succeeded in putting the file to destination. If for any reason the file is not put in destination [maybe due to problems in destination server like space constraint, etc] I need to know that.
Code:
private static boolean putFile(String m_sLocalFile, FtpClient m_client) {
boolean success = false;
int BUFFER_SIZE = 10240;
if (m_sLocalFile.length() == 0) {
System.out.println("Please enter file name");
}
byte[] buffer = new byte[BUFFER_SIZE];
try {
File f = new File(m_sLocalFile);
int size = (int) f.length();
System.out.println("File " + m_sLocalFile + ": " + size + " bytes");
System.out.println(size);
FileInputStream in = new FileInputStream(m_sLocalFile);
OutputStream out = m_client.put(f.getName());
int counter = 0;
while (true) {
int bytes = in.read(buffer);
if (bytes < 0)
break;
out.write(buffer, 0, bytes);
counter += bytes;
System.out.println(counter);
}
out.close();
in.close();
} catch (Exception ex) {
System.out.println("Error: " + ex.toString());
}
return success;
}

I would expect it to throw an IOException. Do you have any reason to believe it doesn't? But you shouldn't be using that class directly, you should be using an ftp: URL and its URLConnection class to do the I/O with, after calling setDoOutput(true).