public class Client {
    private final Socket receiver;
    private final Socket sender;
    
    public Client() {
        receiver = ...;
        sender = ...;
    }
    
    public void receive() {
        while (true) {
            接收...
            send(msg);
        }
    }
    
    public void send(String msg) {
        ...
    }
}

------解决方案--------------------
写了个简单的例子，你试看看能用不，
只是简单的把客户端控制台输出发送在服务器，
服务器把内容打印出来，返回一个字符串给客户端，
并且每5秒钟向所有客户端广播一次系统时间
HTML code
"java"
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;

public class TServerSocket {
    public static void main(String[] args){
        final List<SocketProcessor> socketList = new ArrayList<SocketProcessor>();
        try {
            ServerSocket serverSocket = new ServerSocket(12345);
            Timer timer = new Timer();
            timer.schedule(new TimerTask() {
                @Override
                public void run() {
                    System.out.println("broadcast");
                    for(SocketProcessor processor : socketList)
                        processor.writeToString(Calendar.getInstance().getTime().toGMTString());
                }
            }, 100, 5000);
            while(true){
                Socket socket = serverSocket.accept();
                SocketProcessor processor = new SocketProcessor(socket);
                new Thread(processor).start();
                socketList.add(processor);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

class SocketProcessor implements Runnable{
    private Socket socket;
    private InputStream in = null;
    private OutputStream out = null;
    
    public SocketProcessor(Socket socket){
        this.socket = socket;
        try {
            in = socket.getInputStream();
            out = socket.getOutputStream();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    public void writeToString(String info){
        try {
            out.write(info.getBytes());
            out.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    @Override
    public void run() {
        byte[] data = new byte[1024];
        while(true){
            try {
                int length = in.read(data);
                System.out.println(new String(data, 0, length));
                out.write("recived".getBytes());
                out.flush();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    
}