We Keep Coding

Why downloading image file using input-output stream results broken image files in Java?

I am reading a book on java concurrency in which there is an example of downloading image file from internet. The program uses Files.copy() built-in function to download the image file. Code:
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;
import java.util.concurrent.TimeUnit;
public class TwoFileDownloadingWithJoin {
public static void main(String[] args) {
Thread beatPrinter = new BeatPrinter();
Thread down1 = new FileDownloader("https://secure.meetupstatic.com/photos/event/e/9/f/9/600_464039897.jpeg", "meet1.jpg");
Thread down2 = new FileDownloader("https://secure.meetupstatic.com/photos/event/2/d/0/f/600_464651535.jpeg", "meet2.jpg");
beatPrinter.setName("Beat Printer");
down1.setName("file1 downloader");
down2.setName("file2 downloader");
try {
down1.start();
down2.start();
TimeUnit.MILLISECONDS.sleep(100);
beatPrinter.start();
down1.join();
down2.join();
((BeatPrinter) beatPrinter).kill();
beatPrinter.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Download Complete");
}
}
class BeatPrinter extends Thread {
private volatile boolean live = true;
#Override
public void run() {
while (live) {
printStar("Downloading ");
}
}
void kill() {
live = false;
}
private void printStar(String msg) {
System.out.print(msg);
char[] signs = {'-', '\\', '|', '/'};
for (char s : signs) {
System.out.print(s);
try {
Thread.sleep(300);
System.out.print('\b');
} catch (InterruptedException e) {
e.printStackTrace();
}
}
for (int i = 0; i < msg.length(); i++)
System.out.print('\b');
}
}
class FileDownloader extends Thread {
private String url;
private String fileName;
FileDownloader(String url, String fileName) {
this.url = url;
this.fileName = fileName;
}
#Override
public void run() {
File destinationFile = new File(fileName);
try {
System.out.println("Starting download of " + fileName);
URL fileUrl = new URL(url);
HttpURLConnection connection = (HttpURLConnection) fileUrl.openConnection();
if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
InputStream inputStream = connection.getInputStream();
Files.copy(inputStream, destinationFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
inputStream.close();
} else {
System.out.println("Error: " + connection.getResponseMessage());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
I have modified the program as follows to show download progress:
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.concurrent.TimeUnit;
public class TwoFileDownloadingWithJoin {
public static void main(String[] args) {
Thread down1 = new FileDownloader("https://secure.meetupstatic.com/photos/event/e/9/f/9/600_464039897.jpeg", "meet1.jpg");
Thread down2 = new FileDownloader("https://secure.meetupstatic.com/photos/event/2/d/0/f/600_464651535.jpeg", "meet2.jpg");
down1.setName("file1 downloader");
down2.setName("file2 downloader");
try {
down1.start();
down2.start();
TimeUnit.MILLISECONDS.sleep(100);
down1.join();
down2.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Download Complete");
}
}
class FileDownloader extends Thread {
private String url;
private String fileName;
private double totRead;
private ProgressUpdater progressUpdater;
FileDownloader(String url, String fileName) {
this.url = url;
this.fileName = fileName;
this.progressUpdater = new ProgressUpdater(this, fileName);
}
double getTotRead() {
return totRead;
}
#Override
public void run() {
File destinationFile = new File(fileName);
try {
System.out.println("Starting download of " + fileName);
URL fileUrl = new URL(url);
HttpURLConnection connection = (HttpURLConnection) fileUrl.openConnection();
if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
double fileSize = Double.parseDouble(connection.getHeaderField("content-length"));
InputStream fis = connection.getInputStream();
FileOutputStream fos = new FileOutputStream(destinationFile);
byte[] buffer = new byte[1024];
double currRead;
double totSize = fileSize / 1024.0;
progressUpdater.setTotSize(totSize);
progressUpdater.start();
while ((currRead = fis.read(buffer)) != -1) {
fos.write(buffer);
totRead += currRead / 1024;
}
fis.close();
fos.close();
progressUpdater.kill();
progressUpdater.join();
} else {
System.out.println("Error: " + connection.getResponseMessage());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
class ProgressUpdater extends Thread {
private FileDownloader fileDownloader;
private volatile boolean killed;
private String fileName;
private double totSize;
public ProgressUpdater(FileDownloader fileDownloader, String fileName) {
this.fileDownloader = fileDownloader;
this.fileName = fileName;
killed = false;
}
public void kill() {
killed = true;
}
public void setTotSize(double totSize) {
this.totSize = totSize;
}
#Override
public void run() {
boolean hundredPercent = false;
while (!killed || !hundredPercent) {
double totRead = fileDownloader.getTotRead();
System.out.println(String.format("%s: %.2fKB of %.2fKB downloaded(%.2f%%)", fileName, totRead, totSize, 100 * totRead / totSize));
hundredPercent = (100 * totRead / totSize) > 99.00;
try {
TimeUnit.MILLISECONDS.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
Instead of using Files.copy() I read bytes from input stream and then wrote the bytes to output file. But my approach results broken images. Where is the problem?
Original Image: https://secure.meetupstatic.com/photos/event/e/9/f/9/600_464039897.jpeg
Broken Image: https://imgur.com/UrgafA5

Variable declaration from one class to another

the below codes are working fine(individually) i just want to pass letter[i] value from FindDrive class to Ziputils input file location such that i can zip pendrive data automatically.
FindDrive Class
package com.prosper;
import java.io.File;
public class FindDrive
{
/**
* Application Entry Point
*/
public static void main(String[] args)
{
String[] letters = new String[]{ "A", "B", "C", "D", "E", "F", "G", "H", "I"};
File[] drives = new File[letters.length];
boolean[] isDrive = new boolean[letters.length];
// init the file objects and the initial drive state
for ( int i = 0; i < letters.length; ++i )
{
drives[i] = new File(letters[i]+":/");
isDrive[i] = drives[i].canRead();
}
System.out.println("FindDrive: waiting for devices...");
// loop indefinitely
while(true)
{
// check each drive
for ( int i = 0; i < letters.length; ++i )
{
boolean pluggedIn = drives[i].canRead();
// if the state has changed output a message
if ( pluggedIn != isDrive[i] )
{
if ( pluggedIn ){
System.out.println("Drive "+letters[i]+" has been plugged in");
}
else
System.out.println("Drive "+letters[i]+" has been unplugged");
isDrive[i] = pluggedIn;
}
}
// wait before looping
try { Thread.sleep(100); }
catch (InterruptedException e) { /* do nothing */ }
}
}
}
The ZipUtils Class
package com.prosper;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
public class ZipUtils {
private List <String> fileList;
private static final String OUTPUT_ZIP_FILE = "E:\\appu\\Folder.zip";
private static final String SOURCE_FOLDER = "E:\\appu\\"; //SourceFolder
public ZipUtils() {
fileList = new ArrayList < String > ();
}
public static void main(String[] args) {
ZipUtils appZip = new ZipUtils();
appZip.generateFileList(new File(SOURCE_FOLDER));
appZip.zipIt(OUTPUT_ZIP_FILE);
}
public void zipIt(String zipFile) {
byte[] buffer = new byte[1024];
String source = new File(SOURCE_FOLDER).getName();
FileOutputStream fos = null;
ZipOutputStream zos = null;
try {
fos = new FileOutputStream(zipFile);
zos = new ZipOutputStream(fos);
System.out.println("Output to Zip : " + zipFile);
FileInputStream in = null;
for (String file: this.fileList) {
System.out.println("File Added : " + file);
ZipEntry ze = new ZipEntry(source + File.separator + file);
zos.putNextEntry(ze);
try {
in = new FileInputStream(SOURCE_FOLDER + File.separator + file);
int len;
while ((len = in .read(buffer)) > 0) {
zos.write(buffer, 0, len);
}
} finally {
in.close();
}
}
zos.closeEntry();
System.out.println("Folder successfully compressed");
} catch (IOException ex) {
ex.printStackTrace();
} finally {
try {
zos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
public void generateFileList(File node) {
// add file only
if (node.isFile()) {
fileList.add(generateZipEntry(node.toString()));
}
if (node.isDirectory()) {
String[] subNote = node.list();
for (String filename: subNote) {
generateFileList(new File(node, filename));
}
}
}
private String generateZipEntry(String file) {
return file.substring(SOURCE_FOLDER.length() + 1, file.length());
}
}

To pass data from one class to another, you can do the following:
1) Create an object of the class in your FindDrive class:
ZipUtils utils = new ZipUtils();
2) Pass the value to the method of that class:
utils.zipIt(letter[i])
I have inserted a few statements, which create a new object of ZipUtils class and call the method, however I do suggest you looking into Dependency Injection as well, if you want to improve your code quality here
package com.prosper;
import java.io.File;
public class FindDrive {
/**
* Application Entry Point
*/
public static void main(String[] args) {
String[] letters = new String[] {"A", "B", "C", "D", "E", "F", "G",
"H", "I"};
ZipUtils utils;
File[] drives = new File[letters.length];
boolean[] isDrive = new boolean[letters.length];
// init the file objects and the initial drive state
for (int i = 0; i < letters.length; ++i) {
drives[i] = new File(letters[i] + ":/");
isDrive[i] = drives[i].canRead();
}
System.out.println("FindDrive: waiting for devices...");
// loop indefinitely
while (true) {
// check each drive
for (int i = 0; i < letters.length; ++i) {
boolean pluggedIn = drives[i].canRead();
utils = new ZipUtils();
utils.changeDirectory(letters[i]);
// if the state has changed output a message
if (pluggedIn != isDrive[i]) {
if (pluggedIn) {
System.out.println("Drive " + letters[i] + " has been plugged in");
} else {
System.out.println("Drive " + letters[i] + " has been unplugged");
}
isDrive[i] = pluggedIn;
}
}
// wait before looping
try {
Thread.sleep(100);
} catch (InterruptedException e) { /* do nothing */ }
}
}
}
To make changes to SOURCE_FOLDER after declaration, you need to make sure its not a constant i.e it is not final.
Add a method in ZipUtils:
private static String source_folder = "E:\\appu\\"; //SourceFolder
public void changeDirectory(String zip) {
source_folder = zip + ":\\";
}

How do I copy a pdf into another without losing page sizes and meta information?

My goal is to take out the second page of a pdf and put the contents of another pdf inside of it.
I have taken a look at other answers and I have written the code to delete the template page(page 2.) However, when I copy the other pages into a new book with the first set I get all sorts of insane cropping. It doesn't come out right. I tried to use the setpagesize option but it still doesn't seem like it is working.
Am I going about this in the wrong fashion?
package com.protocase.itexthelper;
import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStamper;
import com.itextpdf.text.pdf.PdfWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
*
* #author davidh
*/
public class ITextHelper {
public static void deletePage(String fileToPrune, int pageToDelete, String newFilePath) {
PdfReader pdfReader = null;
try {
pdfReader = new PdfReader(fileToPrune);
} catch (IOException ex) {
Logger.getLogger(ITextHelper.class.getName()).log(Level.SEVERE, null, ex);
}
if (pdfReader != null) {
List<Integer> pagesToKeep = new ArrayList<Integer>();
//pdfReader.getPages
for (int i = 1; i <= pdfReader.getNumberOfPages(); i++) {
if (i != pageToDelete) {
pagesToKeep.add(i);
}
}
pdfReader.selectPages(pagesToKeep);
}
PdfStamper pdfStamper = null;
try {
pdfStamper = new PdfStamper(pdfReader, new FileOutputStream(newFilePath));
} catch (FileNotFoundException ex) {
Logger.getLogger(ITextHelper.class.getName()).log(Level.SEVERE, null, ex);
} catch (DocumentException | IOException ex) {
Logger.getLogger(ITextHelper.class.getName()).log(Level.SEVERE, null, ex);
} finally {
if (pdfStamper != null) {
try {
pdfStamper.close();
} catch (DocumentException | IOException ex) {
Logger.getLogger(ITextHelper.class.getName()).log(Level.SEVERE, null, ex);
}
}
if (pdfReader != null) {
pdfReader.close();
}
}
}
// -- begin-
public static void main(String[] args) {
String fileToAddTo = "src/com/protocase/itexthelper/examplepdf/BUILD_SHEETS_O4_4USS Rev5.pdf";
String fileWithPageRemoved = "src/com/protocase/itexthelper/examplepdf/BUILD_SHEETS_O4_4USS Rev5-no page 2.pdf";
String fileToAppend = "src/com/protocase/itexthelper/examplepdf/example_component_list.pdf";
String testFile = "src/com/protocase/itexthelper/examplepdf/testfile.pdf";
deletePage(fileToAddTo, 2, testFile);
addPDFToPDF(fileWithPageRemoved, fileToAppend, testFile, 2);
}
/**
* #param originalFilePath Merge multiple pdf into one pdf
* #param fileToInsertPath
*
* #param list of pdf input stream
* #param location where you want to insert the page
* #param outputLocation output stream
* #throws DocumentException
* #throws IOException
*/
public static void addPDFToPDF(String originalFilePath, String fileToInsertPath, String outputLocation, int location) {
OutputStream out = null;
try {
out = new FileOutputStream(new File(outputLocation));
} catch (FileNotFoundException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't find output file location: "+ex);
}
Document document = new Document();
PdfWriter writer = null;
try {
writer = PdfWriter.getInstance(document, out);
} catch (DocumentException ex) {
System.out.println("ITextHelper.addPDFToPDF(): issue getting writer: "+ex);
}
document.open();
if (writer != null) {
PdfContentByte cb = writer.getDirectContent();
PdfReader originalFileReader = null;
try {
originalFileReader = new PdfReader(originalFilePath);
} catch (IOException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't read original file: " + ex);
}
PdfReader fileToAddReader = null;
try {
fileToAddReader = new PdfReader(fileToInsertPath);
} catch (IOException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't read fileToInsert: " + ex);
}
if (fileToAddReader != null && originalFileReader != null) {
for (int i = 1; i <= originalFileReader.getNumberOfPages(); i++) {
if (i == location) {
for (int j = 1; j <= fileToAddReader.getNumberOfPages(); j++) {
document.newPage();
document.setPageSize(fileToAddReader.getPageSize(j));
//import the page from source pdf
PdfImportedPage page = writer.getImportedPage(fileToAddReader, j);
//add the page to the destination pdf
cb.addTemplate(page, 0, 0);
}
}
document.newPage();
document.setPageSize(originalFileReader.getPageSize(i));
PdfImportedPage page = writer.getImportedPage(originalFileReader, i);
cb.addTemplate(page, 0, 0);
}
}
}
closeOutputStream(out, document);
}
// -- end
private static void closeOutputStream(OutputStream out, Document document) {
if (out != null) {
try {
out.flush();
} catch (IOException ex) {
System.out.println("ITextHelper.closeOutputStream(): can't flush outstream: " + ex);
}
document.close();
try {
out.close();
} catch (IOException ex) {
System.out.println("can't close outstream: " + ex);
}
}
}
}

So, I took a look at Bruno Lowagie's book and came to this code. Works perfect actually.
/**
* #param originalFilePath PDF to append to
* #param fileToInsertPath PDF to append
* #param outputFile Where to save to
* #param location where you want to insert the page
*/
public static void mergePDFs(String originalFilePath, String fileToInsertPath, String outputFile, int location) {
PdfReader originalFileReader = null;
try {
originalFileReader = new PdfReader(originalFilePath);
} catch (IOException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't read original file: " + ex);
}
PdfReader fileToAddReader = null;
try {
fileToAddReader = new PdfReader(fileToInsertPath);
} catch (IOException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't read fileToInsert: " + ex);
}
if (originalFileReader != null && fileToAddReader != null) {
// -- Copy
int numberOfOriginalPages = originalFileReader.getNumberOfPages();
Document document = new Document();
PdfCopy copy = null;
try {
copy = new PdfCopy(document, new FileOutputStream(outputFile));
document.open();
for (int i = 1; i <= numberOfOriginalPages; i++) {
if (i == location) {
for (int j = 1; j <= fileToAddReader.getNumberOfPages(); j++) {
copy.addPage(copy.getImportedPage(fileToAddReader, j));
}
}
copy.addPage(copy.getImportedPage(originalFileReader, i));
}
document.close();
} catch (DocumentException | FileNotFoundException ex) {
System.out.println("ITextHelper.addPDFToPDF(): can't read output location: " + ex);
} catch (IOException ex) {
Logger.getLogger(ITextHelper.class.getName()).log(Level.SEVERE, null, ex);
}
}
}

Android webserver shows html pages as text

I am developing a android app which turns the android device into a multithreaded web server the code which i use do not have any error but runs fine and it can be seen through web browser but it shows the source of html file as text rather than full gui.
this is my code..
Jhtts class:
package dolphin.developers.com;
import java.io.File;
import java.io.IOException;
import java.net.InetAddress;
import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.widget.Toast;
import dolphin.devlopers.com.R;
public class JHTTS extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.server);
try {
String IndexFileName = "index.htm";
File documentRootDirectory = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/");
JHTTP j = new JHTTP(documentRootDirectory, 9001, IndexFileName);
j.start();
Toast.makeText(getApplicationContext(), "Server Started!!", 5).show();
Log.d("Server Rooot", "" + documentRootDirectory);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Jhttp class:
package dolphin.developers.com;
import java.io.File;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
public class JHTTP extends Thread {
private File documentRootDirectory;
private String indexFileName = "index.htm";
private ServerSocket server;
private int numThreads = 50;
public JHTTP(File documentRootDirectory, int port, String indexFileName) throws IOException {
if (!documentRootDirectory.isDirectory()) {
throw new IOException(documentRootDirectory
+ " does not exist as a directory");
}
this.documentRootDirectory = documentRootDirectory;
this.indexFileName = indexFileName;
this.server = new ServerSocket(port);
}
public JHTTP(File documentRootDirectory, int port) throws IOException {
this(documentRootDirectory, port, "index.htm");
}
public JHTTP(File documentRootDirectory) throws IOException {
this(documentRootDirectory, 9001, "index.htm");
}
public void run() {
for (int i = 0; i < numThreads; i++) {
Thread t = new Thread(new RequestProcessor(documentRootDirectory, indexFileName));
t.start();
}
System.out.println("Accepting connections on port " + server.getLocalPort());
System.out.println("Document Root: " + documentRootDirectory);
while (true) {
try {
Socket request = server.accept();
request.setReuseAddress(true);
RequestProcessor.processRequest(request);
} catch (SocketException ex) {
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
RequestProcessor:
package dolphin.developers.com;
import java.net.*;
import java.io.*;
import java.util.*;
public class RequestProcessor implements Runnable {
#SuppressWarnings("rawtypes")
private static List pool = new LinkedList( );
private File documentRootDirectory;
private String indexFileName = "index.html";
public RequestProcessor(File documentRootDirectory,
String indexFileName) {
if (documentRootDirectory.isFile( )) {
throw new IllegalArgumentException(
"documentRootDirectory must be a directory, not a file");
}
this.documentRootDirectory = documentRootDirectory;
try {
this.documentRootDirectory
= documentRootDirectory.getCanonicalFile( );
}
catch (IOException ex) {
}
if (indexFileName != null) this.indexFileName = indexFileName;
}
#SuppressWarnings("unchecked")
public static void processRequest(Socket request) {
synchronized (pool) {
pool.add(pool.size( ), request);
pool.notifyAll( );
}
}
public void run( ) {
// for security checks
String root = documentRootDirectory.getPath( );
while (true) {
Socket connection;
synchronized (pool) {
while (pool.isEmpty( )) {
try {
pool.wait( );
}
catch (InterruptedException ex) {
}
}
connection = (Socket) pool.remove(0);
}
try {
String filename;
String contentType;
OutputStream raw = new BufferedOutputStream(
connection.getOutputStream( )
);
Writer out = new OutputStreamWriter(raw);
Reader in = new InputStreamReader(
new BufferedInputStream(
connection.getInputStream( )
),"ASCII"
);
StringBuffer requestLine = new StringBuffer( );
int c;
while (true) {
c = in.read( );
if (c == '\r' || c == '\n') break;
requestLine.append((char) c);
}
String get = requestLine.toString( );
// log the request
System.out.println(get);
StringTokenizer st = new StringTokenizer(get);
String method = st.nextToken( );
String version = "";
if (method.equals("GET")) {
filename = st.nextToken( );
if (filename.endsWith("/")) filename += indexFileName;
contentType = guessContentTypeFromName(filename);
if (st.hasMoreTokens( )) {
version = st.nextToken( );
}
File theFile = new File(documentRootDirectory,
filename.substring(1,filename.length( )));
if (theFile.canRead( )
// Don't let clients outside the document root
&& theFile.getCanonicalPath( ).startsWith(root)) {
DataInputStream fis = new DataInputStream(
new BufferedInputStream(
new FileInputStream(theFile)
)
);
byte[] theData = new byte[(int) theFile.length( )];
fis.readFully(theData);
fis.close( );
if (version.startsWith("HTTP ")) { // send a MIME header
out.write("HTTP/1.0 200 OK\r\n");
Date now = new Date( );
out.write("Date: " + now + "\r\n");
out.write("Server: JHTTP/1.0\r\n");
out.write("Content-length: " + theData.length + "\r\n");
out.write("Content-type: " + contentType + "\r\n\r\n");
out.flush( );
} // end if
// send the file; it may be an image or other binary data
// so use the underlying output stream
// instead of the writer
raw.write(theData);
raw.flush( );
} // end if
else { // can't find the file
if (version.startsWith("HTTP ")) { // send a MIME header
out.write("HTTP/1.0 404 File Not Found\r\n");
Date now = new Date( );
out.write("Date: " + now + "\r\n");
out.write("Server: JHTTP/1.0\r\n");
out.write("Content-type: text/html\r\n\r\n");
}
out.write("<HTML>\r\n");
out.write("<HEAD><TITLE>File Not Found</TITLE>\r\n");
out.write("</HEAD>\r\n");
out.write("<BODY>");
out.write("<H1>HTTP Error 404: File Not Found</H1>\r\n");
out.write("</BODY></HTML>\r\n");
out.flush( );
}
}
else { // method does not equal "GET"
if (version.startsWith("HTTP ")) { // send a MIME header
out.write("HTTP/1.0 501 Not Implemented\r\n");
Date now = new Date( );
out.write("Date: " + now + "\r\n");
out.write("Server: JHTTP 1.0\r\n");
out.write("Content-type: text/html\r\n\r\n");
}
out.write("<HTML>\r\n");
out.write("<HEAD><TITLE>Not Implemented</TITLE>\r\n");
out.write("</HEAD>\r\n");
out.write("<BODY>");
out.write("<H1>HTTP Error 501: Not Implemented</H1>\r\n");
out.write("</BODY></HTML>\r\n");
out.flush( );
}
}
catch (IOException ex) {
}
finally {
try {
connection.close( );
}
catch (IOException ex) {}
}
} // end while
} // end run
public static String guessContentTypeFromName(String name) {
if (name.endsWith(".html") || name.endsWith(".htm")) {
return "text/html";
}
else if (name.endsWith(".txt") || name.endsWith(".java")) {
return "text/plain";
}
else if (name.endsWith(".gif")) {
return "image/gif";
}
else if (name.endsWith(".class")) {
return "application/octet-stream";
}
else if (name.endsWith(".jpg") || name.endsWith(".jpeg")) {
return "image/jpeg";
}
else if (name.endsWith(".png") ) {
return "image/png";
}
else if (name.endsWith(".js")) {
return "text/javascript";
}
else if (name.endsWith(".js")) {
return "text/javascript";
}
else if (name.endsWith(".css")) {
return "text/css";
}
else return "text/plain";
}
} // end RequestProcessor
Please Help...

program to show a progress bar while transferring all files from one server to another in java

i have written a java code to transfer files from one server to another using the concept of socket programming. now in the same code i also want to check for the network connection availability before each file is transferred. i also want that the files transferred should be transferred according to their numerical sequence. And while the files are being transferred the transfer progress of each file i.e the progress percentage bar should also be visible on the screen.
i will really appreciate if someone can help me with the code. i am posting the code i have written for file transfer.
ClientMain.java
import java.io.*;
import java.net.Socket;
import java.net.SocketException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
public class ClientMain {
private DirectoryTxr transmitter = null;
Socket clientSocket = null;
private boolean connectedStatus = false;
private String ipAddress;
String srcPath = null;
String dstPath = "";
public ClientMain() {
}
public void setIpAddress(String ip) {
this.ipAddress = ip;
}
public void setSrcPath(String path) {
this.srcPath = path;
}
public void setDstPath(String path) {
this.dstPath = path;
}
private void createConnection() {
Runnable connectRunnable = new Runnable() {
public void run() {
while (!connectedStatus) {
try {
clientSocket = new Socket(ipAddress, 3339);
connectedStatus = true;
transmitter = new DirectoryTxr(clientSocket, srcPath, dstPath);
} catch (IOException io) {
io.printStackTrace();
}
}
}
};
Thread connectionThread = new Thread(connectRunnable);
connectionThread.start();
}
public static void main(String[] args) {
ClientMain main = new ClientMain();
main.setIpAddress("10.6.3.92");
main.setSrcPath("E:/temp/movies/");
main.setDstPath("D:/tcp/movies");
main.createConnection();
}
}
(DirectoryTxr.java)
import java.io.*;
import java.net.Socket;
import java.net.SocketException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
public class DirectoryTxr {
Socket clientSocket = null;
String srcDir = null;
String dstDir = null;
byte[] readBuffer = new byte[1024];
private InputStream inStream = null;
private OutputStream outStream = null;
int state = 0;
final int permissionReqState = 1;
final int initialState = 0;
final int dirHeaderSendState = 2;
final int fileHeaderSendState = 3;
final int fileSendState = 4;
final int fileFinishedState = 5;
private boolean isLive = false;
private int numFiles = 0;
private int filePointer = 0;
String request = "May I send?";
String respServer = "Yes,You can";
String dirResponse = "Directory created...Please send files";
String fileHeaderRecvd = "File header received ...Send File";
String fileReceived = "File Received";
String dirFailedResponse = "Failed";
File[] opFileList = null;
public DirectoryTxr(Socket clientSocket, String srcDir, String dstDir) {
try {
this.clientSocket = clientSocket;
inStream = clientSocket.getInputStream();
outStream = clientSocket.getOutputStream();
isLive = true;
this.srcDir = srcDir;
this.dstDir = dstDir;
state = initialState;
readResponse(); //starting read thread
sendMessage(request);
state = permissionReqState;
} catch (IOException io) {
io.printStackTrace();
}
}
private void sendMessage(String message) {
try {
sendBytes(request.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
/**
* Thread to read response from server
*/
private void readResponse() {
Runnable readRunnable = new Runnable() {
public void run() {
while (isLive) {
try {
int num = inStream.read(readBuffer);
if (num > 0) {
byte[] tempArray = new byte[num];
System.arraycopy(readBuffer, 0, tempArray, 0, num);
processBytes(tempArray);
}
} catch (SocketException se) {
System.exit(0);
} catch (IOException io) {
io.printStackTrace();
isLive = false;
}
}
}
};
Thread readThread = new Thread(readRunnable);
readThread.start();
}
private void sendDirectoryHeader() {
File file = new File(srcDir);
if (file.isDirectory()) {
try {
String[] childFiles = file.list();
numFiles = childFiles.length;
String dirHeader = "$" + dstDir + "#" + numFiles + "&";
sendBytes(dirHeader.getBytes("UTF-8"));
} catch (UnsupportedEncodingException en) {
en.printStackTrace();
}
} else {
System.out.println(srcDir + " is not a valid directory");
}
}
private void sendFile(String dirName) {
File file = new File(dirName);
if (!file.isDirectory()) {
try {
int len = (int) file.length();
int buffSize = len / 8;
//to avoid the heap limitation
RandomAccessFile raf = new RandomAccessFile(file, "rw");
FileChannel channel = raf.getChannel();
int numRead = 0;
while (numRead >= 0) {
ByteBuffer buf = ByteBuffer.allocate(1024 * 100000);
numRead = channel.read(buf);
if (numRead > 0) {
byte[] array = new byte[numRead];
System.arraycopy(buf.array(), 0, array, 0, numRead);
sendBytes(array);
}
}
System.out.println("Finished");
} catch (IOException io) {
io.printStackTrace();
}
}
}
private void sendHeader(String fileName) {
try {
File file = new File(fileName);
if (file.isDirectory())
return;//avoiding child directories to avoid confusion
//if want we can sent them recursively
//with proper state transitions
String header = "&" + fileName + "#" + file.length() + "*";
sendHeader(header);
sendBytes(header.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
private void sendBytes(byte[] dataBytes) {
synchronized (clientSocket) {
if (outStream != null) {
try {
outStream.write(dataBytes);
outStream.flush();
} catch (IOException io) {
io.printStackTrace();
}
}
}
}
private void processBytes(byte[] data) {
try {
String parsedMessage = new String(data, "UTF-8");
System.out.println(parsedMessage);
setResponse(parsedMessage);
} catch (UnsupportedEncodingException u) {
u.printStackTrace();
}
}
private void setResponse(String message) {
if (message.trim().equalsIgnoreCase(respServer) && state == permissionReqState) {
state = dirHeaderSendState;
sendDirectoryHeader();
} else if (message.trim().equalsIgnoreCase(dirResponse) && state == dirHeaderSendState) {
state = fileHeaderSendState;
if (LocateDirectory()) {
createAndSendHeader();
} else {
System.out.println("Vacant or invalid directory");
}
} else if (message.trim().equalsIgnoreCase(fileHeaderRecvd) && state == fileHeaderSendState) {
state = fileSendState;
sendFile(opFileList[filePointer].toString());
state = fileFinishedState;
filePointer++;
} else if (message.trim().equalsIgnoreCase(fileReceived) && state == fileFinishedState) {
if (filePointer < numFiles) {
createAndSendHeader();
}
System.out.println("Successfully sent");
} else if (message.trim().equalsIgnoreCase(dirFailedResponse)) {
System.out.println("Going to exit....Error ");
// System.exit(0);
} else if (message.trim().equalsIgnoreCase("Thanks")) {
System.out.println("All files were copied");
}
}
private void closeSocket() {
try {
clientSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private boolean LocateDirectory() {
boolean status = false;
File file = new File(srcDir);
if (file.isDirectory()) {
opFileList = file.listFiles();
numFiles = opFileList.length;
if (numFiles <= 0) {
System.out.println("No files found");
} else {
status = true;
}
}
return status;
}
private void createAndSendHeader() {
File opFile = opFileList[filePointer];
String header = "&" + opFile.getName() + "#" + opFile.length() + "*";
try {
state = fileHeaderSendState;
sendBytes(header.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
}
}
private void sendListFiles() {
createAndSendHeader();
}
}
(ServerMain.java)
public class ServerMain {
public ServerMain() {
}
public static void main(String[] args) {
DirectoryRcr dirRcr = new DirectoryRcr();
}
}
(DirectoryRcr.java)
import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
public class DirectoryRcr {
String request = "May I send?";
String respServer = "Yes,You can";
String dirResponse = "Directory created...Please send files";
String dirFailedResponse = "Failed";
String fileHeaderRecvd = "File header received ...Send File";
String fileReceived = "File Received";
Socket socket = null;
OutputStream ioStream = null;
InputStream inStream = null;
boolean isLive = false;
int state = 0;
final int initialState = 0;
final int dirHeaderWait = 1;
final int dirWaitState = 2;
final int fileHeaderWaitState = 3;
final int fileContentWaitState = 4;
final int fileReceiveState = 5;
final int fileReceivedState = 6;
final int finalState = 7;
byte[] readBuffer = new byte[1024 * 100000];
long fileSize = 0;
String dir = "";
FileOutputStream foStream = null;
int fileCount = 0;
File dstFile = null;
public DirectoryRcr() {
acceptConnection();
}
private void acceptConnection() {
try {
ServerSocket server = new ServerSocket(3339);
socket = server.accept();
isLive = true;
ioStream = socket.getOutputStream();
inStream = socket.getInputStream();
state = initialState;
startReadThread();
} catch (IOException io) {
io.printStackTrace();
}
}
private void startReadThread() {
Thread readRunnable = new Thread() {
public void run() {
while (isLive) {
try {
int num = inStream.read(readBuffer);
if (num > 0) {
byte[] tempArray = new byte[num];
System.arraycopy(readBuffer, 0, tempArray, 0, num);
processBytes(tempArray);
}
sleep(100);
} catch (SocketException s) {
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException i) {
i.printStackTrace();
}
}
}
};
Thread readThread = new Thread(readRunnable);
readThread.start();
}
private void processBytes(byte[] buff) throws InterruptedException {
if (state == fileReceiveState || state == fileContentWaitState) {
//write to file
if (state == fileContentWaitState)
state = fileReceiveState;
fileSize = fileSize - buff.length;
writeToFile(buff);
if (fileSize == 0) {
state = fileReceivedState;
try {
foStream.close();
} catch (IOException io) {
io.printStackTrace();
}
System.out.println("Received " + dstFile.getName());
sendResponse(fileReceived);
fileCount--;
if (fileCount != 0) {
state = fileHeaderWaitState;
} else {
System.out.println("Finished");
state = finalState;
sendResponse("Thanks");
Thread.sleep(2000);
System.exit(0);
}
System.out.println("Received");
}
} else {
parseToUTF(buff);
}
}
private void parseToUTF(byte[] data) {
try {
String parsedMessage = new String(data, "UTF-8");
System.out.println(parsedMessage);
setResponse(parsedMessage);
} catch (UnsupportedEncodingException u) {
u.printStackTrace();
}
}
private void setResponse(String message) {
if (message.trim().equalsIgnoreCase(request) && state == initialState) {
sendResponse(respServer);
state = dirHeaderWait;
} else if (state == dirHeaderWait) {
if (createDirectory(message)) {
sendResponse(dirResponse);
state = fileHeaderWaitState;
} else {
sendResponse(dirFailedResponse);
System.out.println("Error occurred...Going to exit");
System.exit(0);
}
} else if (state == fileHeaderWaitState) {
createFile(message);
state = fileContentWaitState;
sendResponse(fileHeaderRecvd);
} else if (message.trim().equalsIgnoreCase(dirFailedResponse)) {
System.out.println("Error occurred ....");
System.exit(0);
}
}
private void sendResponse(String resp) {
try {
sendBytes(resp.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
private boolean createDirectory(String dirName) {
boolean status = false;
dir = dirName.substring(dirName.indexOf("$") + 1, dirName.indexOf("#"));
fileCount = Integer.parseInt(dirName.substring(dirName.indexOf("#") + 1, dirName.indexOf("&")));
if (new File(dir).mkdir()) {
status = true;
System.out.println("Successfully created directory " + dirName);
} else if (new File(dir).mkdirs()) {
status = true;
System.out.println("Directories were created " + dirName);
} else if (new File(dir).exists()) {
status = true;
System.out.println("Directory exists" + dirName);
} else {
System.out.println("Could not create directory " + dirName);
status = false;
}
return status;
}
private void createFile(String fileName) {
String file = fileName.substring(fileName.indexOf("&") + 1, fileName.indexOf("#"));
String lengthFile = fileName.substring(fileName.indexOf("#") + 1, fileName.indexOf("*"));
fileSize = Integer.parseInt(lengthFile);
dstFile = new File(dir + "/" + file);
try {
foStream = new FileOutputStream(dstFile);
System.out.println("Starting to receive " + dstFile.getName());
} catch (FileNotFoundException fn) {
fn.printStackTrace();
}
}
private void writeToFile(byte[] buff) {
try {
foStream.write(buff);
} catch (IOException io) {
io.printStackTrace();
}
}
private void sendBytes(byte[] dataBytes) {
synchronized (socket) {
if (ioStream != null) {
try {
ioStream.write(dataBytes);
} catch (IOException io) {
io.printStackTrace();
}
}
}
}
}
ClientMain.java and DirectoryTxr.java are the two classes under client application. ServerMain.java and DirectoryRcr.java are the two classes under Server application.
run the ClientMain.java and ServerMain.java

You can sort an array using Arrays.sort(...)
ie
String[] childFiles = file.list();
Arrays.sort(childFiles);
As I understand it, this will sort the files in natural order, based on the file name.
You can modify this by passing a custom Comparator...
Arrays.sort(childFiles, new Comparator<File>() {...}); // Fill out with your requirements...
Progress monitoring will come down to your requirements. Do you want to see only the overall progress of the number of files, the individual files, a combination of both?
What I've done in the past is pre-iterated the file list, calculated the total number of bytes to be copied and used a ProgressMonitor to display the overall bytes been copied...
Otherwise you will need to supply your own dialog. In either case, you will need use SwingUtilities.invokeLater to update them correctly.
Check out Concurrency in Swing for more details.
Network connectivity is subjective. You could simply send a special "message" to there server and wait for a response, but this only suggests that the message was sent and a recipt was received. It could just as easily fail when you start transfering the file again...