问题
i am working on a project in java that transfers files from a client to a server. now i need to show the progress bar for each file transfer i.e the progress bar should automatically pop up as each transfer starts. i have made the program to create a progress bar but i am not able to merge it with the client-server programs. i would really appreciate if someone helps me with the loop to be used. thank you.
ClientMain.java
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();
}
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();
}
}
}
}
the client application contains two classes ClientMain.java and DirectoryTxr.java the server application contains two classes ServerMain.java and DirectoryRcr.java
also my code to create a progress bar is
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
public class ProgressBar extends JFrame {
JProgressBar current = new JProgressBar(0, 2000);
int num = 0;
public ProgressBar() {
//exit button
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//create the panel to add the details
JPanel pane = new JPanel();
current.setValue(0);
current.setStringPainted(true);
pane.add(current);
setContentPane(pane);
}
//to iterate so that it looks like progress bar
public void iterate() {
while (num < 2000) {
current.setValue(num);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
}
num += 95;
}
}
//for testing the app
public static void main(String[] arguments) {
ProgressBar frame = new ProgressBar();
frame.pack();
frame.setVisible(true);
frame.iterate();
}
}
回答1:
Swing is a single threaded framework. That means that all interactions with the UI are expected to be made within the context of this thread (AKA The Event Dispatching Thread).
This also means that if you performing any kind of time consuming/long running or blocking process within the EDT, you will prevent it from responding to events or updating the UI.
This is what your code is currently doing.
There are a number of mechanism available to you to over come this, in your case, the simplest is probably to use a SwingWorker
import java.awt.EventQueue;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.SwingWorker;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class ProgressBar extends JFrame {
JProgressBar current = new JProgressBar(0, 100);
int num = 0;
public ProgressBar() {
//exit button
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//create the panel to add the details
JPanel pane = new JPanel();
current.setValue(0);
current.setStringPainted(true);
pane.add(current);
setContentPane(pane);
}
//to iterate so that it looks like progress bar
public void iterate() {
SwingWorker worker = new SwingWorker<Object, Object>() {
@Override
protected Object doInBackground() throws Exception {
while (num < 2000) {
// current.setValue(num);
try {
Thread.sleep(125);
} catch (InterruptedException e) {
}
num += 95;
int p = Math.round(((float)Math.min(num, 2000) / 2000f) * 100f);
setProgress(p);
}
return null;
}
};
worker.addPropertyChangeListener(new PropertyChangeListener() {
@Override
public void propertyChange(PropertyChangeEvent evt) {
String name = evt.getPropertyName();
if ("progress".equals(name)) {
SwingWorker worker = (SwingWorker) evt.getSource();
current.setValue(worker.getProgress());
}
}
});
worker.execute();
}
//for testing the app
public static void main(String[] arguments) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
ProgressBar frame = new ProgressBar();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.iterate();
}
});
}
}
Check out http://docs.oracle.com/javase/tutorial/uiswing/concurrency/ for more details.
Updated with example of dual welding progress bars
If you need to display more then one progress bat, you can simply use the publish and process methods of SwingWorker to accomplish more complex results...
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.SwingWorker;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
*/
public class ProgressBar extends JFrame {
JProgressBar current = new JProgressBar(0, 100);
JProgressBar overall = new JProgressBar(0, 100);
int num = 0;
public ProgressBar() {
//exit button
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//create the panel to add the details
JPanel pane = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
current.setValue(0);
current.setStringPainted(true);
overall.setStringPainted(true);
pane.add(overall, gbc);
pane.add(current, gbc);
setContentPane(pane);
}
//to iterate so that it looks like progress bar
public void iterate() {
SwingWorker worker = new SwingWorker<Object, float[]>() {
@Override
protected void process(List<float[]> chunks) {
float[] progress = chunks.get(chunks.size() - 1); // only want the last one
overall.setValue(Math.round(progress[0] * 100f));
current.setValue(Math.round(progress[1] * 100f));
}
@Override
protected Object doInBackground() throws Exception {
int size = 2000;
int overallSize = size * 10;
int overallProgress = 0;
for (int index = 0; index < 10; index++) {
for (int count = 0; count < size; count++) {
publish(new float[]{
getProgress(overallProgress, overallSize),
getProgress(count, size),
});
overallProgress++;
Thread.sleep(2);
}
}
return null;
}
public float getProgress(int value, int max) {
return (float)value / (float)max;
}
};
worker.execute();
}
//for testing the app
public static void main(String[] arguments) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
ProgressBar frame = new ProgressBar();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.iterate();
}
});
}
}
回答2:
Check out the ProgressMonitorInputStream from the Swing tutorial on Using Progress Bars.
来源：https://stackoverflow.com/questions/17101372/how-to-include-a-progress-bar-in-a-program-of-file-transfer-using-sockets-in-jav