我正在尝试创建服务器和客户端应用程序，其中服务器可以向客户端发送消息，而客户端只能接受来自服务器的消息。
我已经成功实现了这一目标。问题是，client.jar不会收到来自服务器的任何消息。但是在netbean中一切正常。
知道为什么会这样吗？
这是我的完整服务器代码：
public sServerUI() {
super("Server : "+System.getenv("COMPUTERNAME")); // mendapatkan nama komputer
initComponents();
}
public void startListener(){
Random randomGen = new Random();
try{
myPort = randomGen.nextInt(9999);
server = new ServerSocket(myPort);//Bebas portnya, tp nggk boleh sudah terpakai atau pakai random jg bisa
btnListen.setEnabled(false);
while(key == null) {
key = JOptionPane.showInputDialog(this, "Input your Key : ", "Insert Key", JOptionPane.PLAIN_MESSAGE);
}
if(key.equals("")) {
key = "Random";
txtMessage.setText(txtMessage.getText()+"Invalid key inputted, key automatically set to '"+key+"'\n");
} else txtMessage.setText(txtMessage.getText()+"Key set to '"+key+"'\n");
} catch (IOException e) {//Kalau sudah terpakai muncul error
JOptionPane.showMessageDialog(this, "Could not listen at " + myPort);
//Gagal, keluarin info
} finally{
myPort = server.getLocalPort();
lblPort.setText("Port: "+myPort);
System.out.println("Port: "+myPort);
}
acceptClient.start();
}
public void windowClosing(WindowEvent e){
try {
server.close();
for (int i=0;i<numberOfClient;i++){
socketIn[i].close();
socketOut[i].close();
}
} catch (IOException ex) {
System.out.println("Error "+ex.getMessage());
}
}
class Accepter extends Thread{
@Override
public void run(){
while (true){
try{
client[numberOfClient] = server.accept();
numberOfClient++;
lblStatus.setText("Status: "+numberOfClient+" client(s) connected");
Handler handleClient = new Handler(numberOfClient-1);
handleClient.start();
} catch (IOException e) {
JOptionPane.showMessageDialog(null, "Accept failed: " + myPort);
}
}
}
}
class Handler extends Thread{
private int arr;
Handler(int ar){
arr = ar;
try{
socketIn[arr] = new BufferedReader(new InputStreamReader(client[arr].getInputStream()));
socketOut[arr] = new PrintWriter(client[arr].getOutputStream(), true);
} catch (IOException e) {
JOptionPane.showMessageDialog(null, "Read failed");
}
}
@Override
public void run(){
while (true){
try{
if (socketIn[arr].ready()){
System.out.println("Reading...");
line = socketIn[arr].readLine();
if (!txtMessage.getText().equals("")){
txtMessage.setText(txtMessage.getText()+"\n");
//broadcast message ke client2 lain
}
txtMessage.setText(txtMessage.getText()+"Client "+(arr+1)+": "+line);
for (int i=0;i<numberOfClient;i++){
if (i!=arr){//jgn kembaliin ke client yg kirim
socketOut[i].println("Client "+(arr+1)+": "+line);
}
}
}
} catch (IOException e) {
System.out.println("Read failed");
}
}
}
}
private void btnListenActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
startListener();
}
private void sendData(String data) {
for (int j=0;j<numberOfClient;j++){
socketOut[j].println(data);
}
}
private void btnSendActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
if(numberOfClient > 0) {
int packetIndex = 1;
String ext = getExt(filePath, '.');
String sData = "start"+pemisahString+fByte.length+pemisahString+ext+pemisahString; //menaruh kata kunci 'start' dan ukuran file di awal message, serta extensionnya
sendData(sData);
sData = "";
int k = 0;
for(int i = 0; i < fByte.length; i++) {
if(k >= Math.ceil((double)fByte.length/10.0)) {
k = 0;
sData = rc4(key, sData);
sendData(Integer.toString(packetIndex)+pemisahString+sData);
txtMessage.setText(txtMessage.getText()+"packet-"+packetIndex+" sent ! isi : "+revertToString(rc4(key,revertToString(sData)))+"\n");
packetIndex++;
sData = "";
}
sData += fByte[i];
sData += pemisahString;
k++;
if(i == fByte.length-1) {
sData = rc4(key, sData);
sendData(Integer.toString(packetIndex)+pemisahString+sData);
txtMessage.setText(txtMessage.getText()+"packet-"+packetIndex+" sent ! isi : "+revertToString(rc4(key,revertToString(sData)))+"\n");
packetIndex++;
sData = "";
}
}
sData = "end"+pemisahString;
sendData(sData);
txtMessage.setText(txtMessage.getText() + "Done ! divided into "+k+" piece(s) per packet\n");
} else JOptionPane.showMessageDialog(this, "No Client Connected !", "Error", JOptionPane.ERROR_MESSAGE);
}
private void fileBtnActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("d:/Kul/Smstr 6/Kripto n Steno/Stream Cipher/"));
int returnVal = chooser.showOpenDialog(this);
if(returnVal == JFileChooser.APPROVE_OPTION) {
filePath = chooser.getSelectedFile().getPath();
try {
inputFile = new File(filePath);
fIn = new FileInputStream(inputFile);
fByte = new byte[(int)inputFile.length()];
System.out.println("file size : "+(int)inputFile.length()+" byte(s)");
System.out.print("Isi file : ");
fIn.read(fByte);
fIn.close();
for(int i = 0; i < fByte.length; i ++) {
System.out.print(fByte[i]+" ");
}
System.out.print("end of file\n");
String stringBuatDitampilin = getExt(filePath, (char)92);
txtMessage.setText(txtMessage.getText() + "'" + stringBuatDitampilin + "' Loaded !\n");
btnSend.setEnabled(true);
//fIn.close();
//JOptionPane.showMessageDialog(this, "File Loaded !", "Success", JOptionPane.INFORMATION_MESSAGE);
} catch(java.io.IOException e) {
JOptionPane.showMessageDialog(this, e.toString(), "IO Error", JOptionPane.ERROR_MESSAGE);
}
}
}
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(sServerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new sServerUI().setVisible(true);
}
});
}
这是我完整的客户代码：
public sClientUI() {
super("Client");
initComponents();
}
public void listenSocket(){
//Create socket connection
try{
socket = new Socket(txtHost.getText(), Integer.parseInt(txtPort.getText()));
socketOut = new PrintWriter(socket.getOutputStream(), true);
socketIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
txtMessage.setText(txtMessage.getText()+"Succesfully connected to "+txtHost.getText()+" !\n");
while(key == null) {
key = JOptionPane.showInputDialog(this, "Input your Key : ", "Insert Key", JOptionPane.PLAIN_MESSAGE);
}
if(key.equals("")) {
key = "Random";
txtMessage.setText(txtMessage.getText()+"Invalid key inputted, key automatically set to '"+key+"'\n");
} else txtMessage.setText(txtMessage.getText()+"Key set to '"+key+"'\n");
txtHost.setEditable(false);
txtPort.setEditable(false);
btnConnect.setEnabled(false);
myListener = new Timer(250, readLine);
myListener.start();
} catch (UnknownHostException e) {
JOptionPane.showMessageDialog(this, "Unknown host: "+e.getMessage(), "Unknown Hostname", JOptionPane.ERROR_MESSAGE);
} catch (IOException e) {
JOptionPane.showMessageDialog(this, "Either your hostname is wrong, or you entered wrong port number\n"+e.getMessage(),"Input Error", JOptionPane.ERROR_MESSAGE);
} catch (NumberFormatException e) {
JOptionPane.showMessageDialog(this, e.getMessage(),"Invalid Port Number", JOptionPane.ERROR_MESSAGE);
}
}
public void windowClosing(WindowEvent e){
try {
socket.close();
socketIn.close();
socketOut.close();
} catch (IOException ex) {
System.out.println("Error "+ex.getMessage());
}
}
ActionListener readLine = new ActionListener(){
@Override
public void actionPerformed(ActionEvent ae) {
try{
if (socketIn.ready()){
String tempReceiver;
if((tempReceiver = socketIn.readLine()) != null) {
exStr(tempReceiver); //untuk memotong-motong string dan meng-create file baru
}
}
} catch (IOException e) {
System.out.println("Read failed");
}
}
};
private void btnConnectActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
listenSocket();
}
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(sClientUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new sClientUI().setVisible(true);
}
});
}
答案 0 :(得分：0)
你的代码缺少一些重要的和平。例如进口。他们向我们展示了您使用的库，并为我们提供了进行一些研究的机会。
1）例如，行：
myListener = new Timer(250, readLine);
它不能是java.util.Timer，因为这个类没有构造函数（long / int，ActionListener）。可能这个电话只运行一次而不是多次，但我无法知道并告诉你。
2）另一个例子：你有一行
acceptClient.start();
我只能假设有一个实例变量
Accepter acceptClient = new Accepter();
但它也可以指一个完全不同的类，它的工作方式不同。
3）回到我的第一个例子：
你正在进行某种民意调查。这不是java中的好风格，因为Java Thready是针对阻塞线程而优化设计的。使用这样的代码块（未经测试;受到服务器代码的启发）
class ClientThread extends Thread{
@Override
public void run(){
try{
String tempReceiver;
while ((tempReceiver = socketIn.readLine()) != null) {
exStr(tempReceiver);
}
} catch (IOException e) {
System.out.println("Read failed");
}
}
}
在这种情况下，您不需要轮询，您可以立即做出回应。这会消耗更少的CPU。 一个完全不同的选择是使用Java NIO，它更适合单线程应用程序（或者让它称为几个线程）。
一些偏离主题的评论：
OT 1）
调用诸如JOptionPane.showMessageDialog()和setText()之类的Swing函数对于线程来说是危险的。 Swing本身不是线程安全的。你应该使用EventQueue.invokeLater()包装器。我的最爱：SwingUtils.invokeLater()
OT 2）
让变量tempReceiver class-global（我假设这是因为我看不到任何声明）也是危险的，因为你可能在其他地方使用它并且可能在readLine()和{exStr()期间完全覆盖它{1}}在另一个线程中调用（如果Timer是Swing实现，它运行一个额外的线程）。
OT 3）
你说＆＃34; .jar客户端和服务器已相互连接＆＃34;。这是否意味着您有两个打开的控制台窗口，每个窗口中都运行java -jar命令？如果没有，您可能会错过一些重要的控制台输出（可能是异常）。
java的windows发行版有2个java运行器：javaw.exe，在资源管理器中双击.jar文件时调用它。 java.exe也运行你的程序，但也会打开一个控制台窗口，显示System.out.println等的输出。这个控制台对于调试非常重要。它显示与NetBeans或Eclipse中的Debug窗口相同的输出。
答案 1 :(得分：0)
解决
这是因为我使用一些密码算法加密消息 我发送字节为字符串 控制台无法读取某些加密字符，因此程序无法执行某些键操作来处理消息
无论如何，谢谢大家：）