Socket在eclipse中运行失败

Question

问题遇到的现象和发生背景

package Serversocket;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Serversocket_Android {

    private static final int PORT = 9999;  //设置端口号
    private List<Socket> mList = new ArrayList<Socket>(); //用ArrayList实现多个用户
    private ServerSocket server = null;//服务器
    private ExecutorService mExecutorService = null;
    private String receiveMsg;//接受的信息
    private String sendMsg;//发送的信息

    public static void main(String[] args) {
        new Serversocket_Android();
    }

    public Serversocket_Android() {
        try {
            server = new ServerSocket(PORT);
            mExecutorService = Executors.newCachedThreadPool();
            System.out.println("服务器已启动...");
            Socket client = null;
            while (true) {
                client = server.accept();
                mList.add(client);//客户端加入ArrayList
                mExecutorService.execute(new Service(client));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    class Service implements Runnable {
        private Socket socket;
        private BufferedReader in = null;
        private PrintWriter printWriter=null;

        public Service(Socket socket) {
            this.socket = socket;
            try {
                printWriter = new PrintWriter(new BufferedWriter(new OutputStreamWriter( socket.getOutputStream(), "UTF-8")), true);
                in = new BufferedReader(new InputStreamReader(
                        socket.getInputStream(),"UTF-8"));
                printWriter.println("成功连接服务器"+"（服务器发送）");
                System.out.println("成功连接服务器");
            } catch (IOException e) {
                e.printStackTrace();
            }

        }

        @Override
        public void run() {
            try {
                while (true) {
                    if ((receiveMsg = in.readLine())!=null) {
                        System.out.println("receiveMsg:"+receiveMsg);
                        if (receiveMsg.equals("0")) {
                            System.out.println("客户端请求断开连接");
                            printWriter.println("服务端断开连接"+"（服务器发送）");
                            mList.remove(socket);
                            in.close();
                            socket.close();
                            break;
                        } else {
                            sendMsg = "我已接收：" + receiveMsg + "（服务器发送）";
                            printWriter.println(sendMsg);
                        }
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

问题相关代码，请勿粘贴截图

运行结果及报错内容

java.net.BindException: Address already in use: bind
    at java.base/sun.nio.ch.Net.bind0(Native Method)
    at java.base/sun.nio.ch.Net.bind(Net.java:550)
    at java.base/sun.nio.ch.Net.bind(Net.java:539)
    at java.base/sun.nio.ch.NioSocketImpl.bind(NioSocketImpl.java:643)
    at java.base/java.net.ServerSocket.bind(ServerSocket.java:396)
    at java.base/java.net.ServerSocket.<init>(ServerSocket.java:282)
    at java.base/java.net.ServerSocket.<init>(ServerSocket.java:173)
    at Serversocket.Serversocket_Android.<init>(Serversocket_Android.java:31)
    at Serversocket.Serversocket_Android.main(Serversocket_Android.java:26)

我的解答思路和尝试过的方法

我想要达到的结果

Answer 1

端口9999被重复绑定了，有其他进程在占用 用cmd排查一下 不懂可以问我