Java Server

import java.io.BufferedInputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class Server implements Runnable {

ServerSocket serverSocket;

public static void main(String[] args) throws IOException {
new Thread(new Server()).start();
}

public Server() {
try {
serverSocket = new ServerSocket(7777);
} catch (IOException e) {
e.printStackTrace();
}
}

@Override
public void run() {
Socket socket;
BufferedInputStream inputStream;
System.out.println("伺服器已經啟動");

while (true) {
socket = null;
try {
synchronized (serverSocket) {
socket = serverSocket.accept();
}
socket.setSoTimeout(15000);
inputStream = new BufferedInputStream(socket.getInputStream());
byte[] b = new byte[1024];
String data = "";
int length;
while ((length = inputStream.read(b)) > 0) {
data = new String(b, 0, length);
}
if (data.equals("Exit")) {
inputStream.close();
inputStream = null;
socket.close();
serverSocket.close();
System.out.println("伺服器已關閉");
break;
} else {
System.out.println(data);
inputStream.close();
inputStream = null;
socket.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}