Question

这是我的服务器。顺便说一句，我正在使用JFrame。实际上，当我在PC 1中运行服务器然后是pc 2和PC 3上的客户端时，我有很多PC .PC 3客户端连接但服务器无法接收消息。虽然pc 2客户端已连接。

 package server;
 import java.net.*;
 import java.io.*;

public class FrmServer extends javax.swing.JFrame {

ServerSocket providerSocket;
Socket connection=null;
ObjectOutputStream out;
ObjectInputStream in;
String message;

//To run the connection
public void run(){

用于连接

    try{
        providerSocket = new ServerSocket(9090);
        msgArea.append("Waiting for connection....");
        connection = providerSocket.accept();

        out = new ObjectOutputStream(connection.getOutputStream());
        out.flush();

        in = new ObjectInputStream(connection.getInputStream());
        sendmessage("Connection is successful...");

        while(true){
           message = (String)in.readObject();

           if(!message.isEmpty())
               msgArea.append("\nClient: "+message);
        }

    }
    catch(Exception e){

    }

}

public void sendmessage(String msg){

    try{
        out.writeObject(msg);
        out.flush();
        msgArea.append("\nServer: "+msg);
    }catch(Exception e){

    }
}

/**
 * Creates new form FrmServer
 */
public FrmServer() {
    initComponents();
}

private void btnSendActionPerformed(java.awt.event.ActionEvent evt) {                                        
    // TODO add your handling code here:
    sendmessage(txt.getText());
} 
public static void main(String args[]) {
FrmServer s = new FrmServer();
    s.setVisible(true);
    s.run();

}

客户端

package client;

import java.net.*;
import java.io.*;

public class FrmClient extends javax.swing.JFrame {

Socket requestSocket;
ObjectInputStream in;
ObjectOutputStream out;
String message;
/**
 * Creates new form FrmClient
 */
public FrmClient() {
    initComponents();
}

public void run(){

    try{
        requestSocket = new Socket("10.99.225.12",9090);
        msgArea.append("Connected to the server...");

        out = new ObjectOutputStream(requestSocket.getOutputStream());
        out.flush();

        in = new ObjectInputStream(requestSocket.getInputStream());

        while(true){
           message = (String)in.readObject(); 

           if(!message.isEmpty());
               msgArea.append("\nServer: "+message);
        }
    }
    catch(Exception e){

    }

}

public void sendmessage(String msg){

    try{
        out.writeObject(msg);
        out.flush();

        msgArea.append("\nClient: "+msg);
    }
    catch(Exception e){

    }

}

private void btnSendActionPerformed(java.awt.event.ActionEvent evt) {                                        
    // TODO add your handling code here:
    sendmessage(txt.getText());
}  
private void formWindowClosing(java.awt.event.WindowEvent evt) {                                   
    // TODO add your handling code here:

    try{
        sendmessage("Got to go.. Goodbye!");
        in.close();
        out.close();
        requestSocket.close();
    }
    catch(Exception e){

    }

} 
public static void main(String args[]) {
FrmClient c = new FrmClient();
    c.setVisible(true);
    c.run();
}

Answer 1

您必须为每个套接字（客户端）创建一个线程，然后处理它们。

到目前为止，我发现，只有一个连接，因为您只初始化connection一次。

您可以创建一个列表，包含所有套接字以及从/向其输入/输出流写入/读取。

Answer 2

您需要一个专用线程来持续监听连接。

接受连接后，为每个接受的连接创建两个线程，一个用于读取传入的数据，另一个用于将数据写入套接字。

这是对代码的简单修改，尽管可以用更好的方式编写。

让您的JFrame类实现Runnable。

public class FrmServer extends javax.swing.JFrame implements Runnable

在JFrame类中实现run方法

@Override
public void run() {
    while (true) {
        try {
            msgArea.append("Waiting for connection....");
            connection = providerSocket.accept();
            new ConnectionWriter(connection, msgArea).start();
            new ConnectionReader(connection, msgArea).start();
        } catch (IOException ex) {
            System.err.out(ex);
        }
    }
}

创建一个写入套接字的线程

public class ConnectionWriter extends Thread {

    ObjectOutputStream out;
    Socket connection;
    JTextArea msgArea;

    public ConnectionWriter(Socket connection, JTextArea msgArea) {
        this.connection = connection;
        this.msgArea = msgArea;
    }

    @Override
    public void run() {
        try {
            out = new ObjectOutputStream(connection.getOutputStream());
            out.flush();
            sendmessage("Connection is successful...");
        } catch (IOException e) {
            System.out.println(e);
        }
    }

    public void sendmessage(String msg) {

        try {
            out.writeObject(msg);
            out.flush();
            msgArea.append("\nServer: " + msg);
        } catch (IOException e) {
            System.err.println(e);
        }
    }
}

创建一个从套接字读取的线程。

public class ConnectionReader extends Thread {

    ObjectInputStream in;
    Socket connection;
    JTextArea msgArea;

    public ConnectionReader(Socket connection, JTextArea msgArea) {
        this.connection = connection;
        this.msgArea = msgArea;
    }

    @Override
    public void run() {
        try {
            in = new ObjectInputStream(connection.getInputStream());
            while (true) {
                String message = (String) in.readObject();

                if (!message.isEmpty()) {
                    msgArea.append("\nClient: " + message);
                }
            }
        } catch (IOException ex) {
            System.err.out(e);
        }
    }

}

如何用1台服务器做多个客户端？

2 个答案: