【发布时间】：2017-01-05 21:06:52
【问题描述】：
我正在为在服务器和客户端系统上运行的游戏创建聊天，当然还有在服务器客户端系统上运行的游戏，但我无法让我的多线程程序运行，我将在下面解释如何.我可以说的是服务器客户端系统在单线程时工作。
首先，我的连接类：
public class Connection {
private Server server;
private Client client;
private boolean serverChosen;
public Connection(){
server = new Server();
this.serverChosen = true;
}
public Connection(String IP){
client = new Client(IP);
this.serverChosen = false;
}
public synchronized void sendObjects(Object obj) throws IOException{
if(serverChosen){
server.sendObjects(obj);
}else{
client.sendObjects(obj);
}
}
public synchronized Object receiveObjects() throws ClassNotFoundException, IOException{
if(serverChosen){
return server.receiveObjects();
}else{
return client.receiveObjects();
}
}
public Object waitForObject() throws ClassNotFoundException, IOException{
int i = 0;
Object obj;
while(true){
obj = receiveObjects();
i++;
if(obj != null || i >= 100){
return obj;
}
}
}
}
服务器和客户端类：
public class Server implements Serializable{
private ObjectOutputStream output;
private ObjectInputStream input;
private ServerSocket server;
private Socket connection;
//constructor
public Server(){
try{
server = new ServerSocket(8790, 10); //8798 is a dummy port for testing, this can be changed. The 100 is the maximum people waiting to connect.
try{
//Trying to connect and have conversation
waitForConnection();
setupStreams();
}catch(EOFException eofException){
}
} catch (IOException ioException){
ioException.printStackTrace();
}
}
//wait for connection, then display connection information
private void waitForConnection() throws IOException{
connection = server.accept();
}
//get stream to send and receive data
private void setupStreams() throws IOException{
output = new ObjectOutputStream(connection.getOutputStream());
output.flush();
input = new ObjectInputStream(connection.getInputStream());
}
public ObjectOutputStream getOutput(){
return output;
}
public ObjectInputStream getInput(){
return input;
}
public void sendObjects(Object obj) throws IOException{
output.writeObject(obj);
output.flush();
}
public Object receiveObjects() throws IOException, ClassNotFoundException{
return input.readObject();
}
}
public class Client extends JFrame implements Serializable{
private static final long serialVersionUID = 1L;
private ObjectOutputStream output;
private ObjectInputStream input;
private String serverIP;
private Socket connection;
private boolean next = true;
//constructor
public Client(String host){
serverIP = host;
try{
connectToServer();
setupStreams();
}catch(EOFException eofException){
}catch(IOException ioException){
ioException.printStackTrace();
}
}
public Client(){
serverIP = "127.0.0.1";
try{
connectToServer();
if(next){
setupStreams();
}
}catch(EOFException eofException){
//t.append("Connection was terminated");
}catch(IOException ioException){
ioException.printStackTrace();
}
}
//connect to server
private void connectToServer(){
int i = 0;
do {
try {
connection = new Socket(InetAddress.getByName(serverIP), 8790);
next = true;
} catch (IOException e) {
e.printStackTrace();
JOptionPane.showMessageDialog(null, "Server was not found, The program will try again in 1 second; number of tries left: " + (10-i));
next = false;
try {
Thread.sleep(1000);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
i++;
}
}while(!next && i<=10);
if(!next){
JOptionPane.showMessageDialog(null, "Unable to connect to the server. Make sure the I.P. adress is correct, the ports are not blocked, or a firewall has not prevented connections.... IDK man... it's just me and all of this code... maybe the server isn't even running??");
}
}
//set up streams
private void setupStreams() throws IOException{
output = new ObjectOutputStream(connection.getOutputStream());
output.flush();
input = new ObjectInputStream(connection.getInputStream());
}
public ObjectOutputStream getOutput(){
return output;
}
public ObjectInputStream getInput(){
return input;
}
public void sendObjects(Object obj) throws IOException{
output.writeObject(obj);
output.flush();
}
public Object receiveObjects() throws ClassNotFoundException, IOException{
return input.readObject();
}
}
我运行一切的类是 Frame 类：
public class Frame implements ActionListener{
private int width;
private int height;
private JFrame jframe;
private Board board;
private JTextArea textBox;
private JScrollPane pane;
private Connection connection;
private JTextArea userText;
private JScrollPane userPane;
private JButton send;
private NetworkReceiver net;
public Frame(int width, int height, Connection connection, Board player, Board opponent){
this.width = width;
this.height = height;
this.connection = connection;
board = new Board(player, opponent);
init();
textBox = new JTextArea("CHAT WINDOW");
textBox.setWrapStyleWord(true);
textBox.setLineWrap(true);
textBox.setBackground(Color.GRAY);
textBox.setBounds(height, 0, width - (height) - 20, height-40);
textBox.setEditable(false);
userText = new JTextArea("Enter Messages Here");
userText.setWrapStyleWord(true);
userText.setLineWrap(true);
userText.setBackground(Color.WHITE);
userText.setBounds(height, height-40, width - (height) - 20, 40);
pane = new JScrollPane(textBox,
ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
pane.setBounds(height, 0, width - (height), height-40);
userPane = new JScrollPane(userText,
ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
userPane.setBounds(height, height-40, width - (height) - 20, 40);
send = new JButton();
send.setIcon(Utility.getImageIcon(Utility.getBufferedImage(Assets.send)));
send.setBounds(width - 20, height - 40, 20, 40);
send.addActionListener(this);
send.setBackground(Color.WHITE);
jframe = new JFrame();
jframe.setBackground(Color.DARK_GRAY);
jframe.getContentPane().setPreferredSize(new Dimension(width, height));
jframe.setLayout(null);
jframe.pack();
jframe.setLocationRelativeTo(null);
jframe.add(pane);
jframe.add(userPane);
jframe.add(send);
for(Space[] s: board.getSpaces()){
for(Space space: s){
jframe.add(space);
}
}
for(Space[] s: board.getSpaces()){
for(Space space: s){
space.addActionListener(this);
}
}
for(Space[] s: board.getSpaces()){
for(Space space: s){
if(space.getTile() != null){
space.setBackground(space.getTile().getColor());
}
}
}
for(Space[] s: board.getSpaces()){
for(Space space: s){
if(space.getPiece() != null){
space.setIcon(Utility.getImageIcon(space.getPiece().getImage()));
}
}
}
jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jframe.setVisible(true);
net = new NetworkReceiver(connection, this);
net.start();
}
private void init(){
//stuff
}
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == send){
send();
}
}
private synchronized void send() {
String message = "YOU- " + userText.getText();
userText.setText("");
String totalMessage = textBox.getText();
textBox.setText(totalMessage + "\n" + message);
new NetworkSender(connection, message).start();
}
public synchronized void showMessage(String s){
String totalMessage = "Opponent- " + textBox.getText();
textBox.setText(totalMessage + "\n" + s);
}
我不想在上面的构造函数中删除更多内容，以防它以某种方式导致问题（我对此表示怀疑，但因为我找不到比抱歉更安全的问题）
这里是 NetworkSender 和 NetworkReceiver 类：
public class NetworkSender extends Thread{
private Connection c;
private String msg;
public NetworkSender(Connection c, String msg){
this.c = c;
this.msg = msg;
}
public void run(){
try {
System.out.println("Trying to send");
c.sendObjects(msg);
System.out.println("Sent");
} catch (IOException e) {
e.printStackTrace();
}
}
}
public class NetworkReceiver extends Thread{
private Connection c;
private boolean running = true;
private Frame f;
public NetworkReceiver(Connection c, Frame f){
this.c = c;
this.f = f;
}
public void run(){
while(running){
System.out.println("running");
Object obj = null;
try {
obj = c.receiveObjects();
System.out.println("received");
} catch (ClassNotFoundException e) {
System.out.println("failed - class exception");
e.printStackTrace();
} catch (IOException e) {
System.out.println("failed - IO exception");
e.printStackTrace();
running = false;
}
if(obj != null){
if(obj instanceof String){
f.showMessage((String)obj);
}
}
}
}
public void kill(){
running = false;
}
}
确切的中断点在 NetworkSender 类中。在控制台中，我收到“尝试发送”但从未“发送”。这让我认为我设置了错误的线程，线程不知何故无法相互通信（发送者和接收者线程），或者服务器/客户端系统未正确完成多线程。
我已经广泛地查找了这个问题，但在任何地方都找不到有效的解决方案，所以如果有我看过的解决方案，我深表歉意。如果一切正常，我可以在需要时发布我的连接、服务器和客户端类，但我假设它们是正常的，因为它们在 EDT 上工作。由于我在网上搜索了将近 4 个小时，我问如果您认为这是一个重复的问题，请先评论一个链接，因为我几乎可以肯定我已经看过它了，哈哈。
【问题讨论】：
-
这一切看起来都很可疑，但你没有展示最重要的东西：连接。您可能在连接类中使用粗略同步使线程死锁（例如，NetworkReceiver 在 Connection 上持有监视器阻止其他所有内容）。整个代码对我来说看起来很可疑，扩展了 Thread 并为每条消息创建了一个新的 NetworkSender，所有的消息都敲响了警钟。
-
@Durandal，我会发布我的连接和服务器/客户端类。死锁听起来是可能的，但我对套接字的了解还不够，无法确定。我希望新代码可以帮助你帮助我哈哈
-
很明显，您在同一个对象（连接）上同步发送和接收。这意味着当 NetworkReceiver 等待接收数据时，什么都没有可以发送。我会重新考虑整个设计，特别是仔细考虑在哪个对象上同步的内容。还要重新考虑放置方法 - 我有理由期望 Connection 类代表一个连接的 endpoint，在客户端/服务器之间没有切换逻辑。如果您将 Connection 建立在 Socket 对象的基础上，那么差异的需求就消失了。
-
连接要么是服务器，要么是客户端。它永远不会在它们之间切换。我是这样实现的，因为这样我就不需要制作同一个游戏的 2 个不同版本。
标签： java multithreading sockets server