连接被拒绝尝试连接到localhost上的套接字时出错

我正在尝试使用PC上的Java服务器和作为客户端的Android应用程序来设置一个简单的服务器 - 客户端应用程序 . 它们都连接到同一个Wi-Fi网络 . 我试图让客户端连接到服务器套接字时遇到问题 . 我使用“localhost”作为服务器的IP，并确保服务器正在运行并等待端口60101上的连接 . 该端口未被任何其他应用程序使用，并且正在侦听 . 当我尝试连接此行时，客户端抛出连接被拒绝错误：

connection = new Socket(serverAddress,serverPort);// ("localhost", 60101)

这是我的服务器代码：

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class Main {

    private static final int portNumber = 60101;

    public static void main(String[] args) {

        ServerSocket serverSocket = null;

        try {
            //starting server
            System.out.println("Server starting at port number: "+portNumber);
            serverSocket = new ServerSocket(portNumber);

            //client connecting
            System.out.println("Waiting for clients to connect");
            Socket socket = serverSocket.accept();
            System.out.println("Client has connected.");

            //Send message to the client
            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
            bw.write("this is a message from the server");
            bw.newLine();
            bw.flush();

            //Receive message from client
            BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            String data;
            while((data = br.readLine()) != null ){
                System.out.println("Message from the client: " + data);

            }
            System.out.println("Server has ended");

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Android MainActivity.java：

package johnedchristensen.androidclienttestapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    TextView showMessageText;
    Button buttonConnect;
    String serverAddress = "localhost";
    int portNumber = 60101;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        showMessageText = (TextView) findViewById(R.id.textView);
        buttonConnect = (Button) findViewById(R.id.button);

        buttonConnect.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                Client myClient = new Client(serverAddress, portNumber, showMessageText);
                myClient.execute();
            }
        });
    }
}

Android Client.java：

package johnedchristensen.androidclienttestapplication;

import android.os.AsyncTask;
import android.widget.TextView;
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;



public class Client extends AsyncTask<Void,Void,Void>{
    private String serverAddress;
    private int serverPort;
    private TextView messageDisplay;
    private Socket connection;
    private String statusMessage = "";

    Client(String address, int port, TextView message){
        serverAddress = address;
        serverPort = port;
        this.messageDisplay = message;

    }

    @Override
    protected Void doInBackground(Void... params) {


        try{
            //connection
            statusMessage += "Attempting to connect... \n";
            connection = new Socket(serverAddress,serverPort);
            statusMessage += "Connected to: " + connection.getInetAddress().getHostName();

        }catch(EOFException eofException){
            statusMessage +="\n Error Connecting";
        }catch(IOException ioException){
            statusMessage +="\n Error Connecting";
            ioException.printStackTrace();
        }
        return null;
    }
    @Override
    protected void onPostExecute(Void result) {
        messageDisplay.setText(statusMessage);
        super.onPostExecute(result);
    }

}

连接拒绝错误：

W/System.err: java.net.ConnectException: Connection refused
 W/System.err:     at java.net.PlainSocketImpl.socketConnect(Native Method)
 W/System.err:     at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:334)
 W/System.err:     at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:196)
 W/System.err:     at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:178)
 W/System.err:     at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:356)
 W/System.err:     at java.net.Socket.connect(Socket.java:586)
 W/System.err:     at java.net.Socket.connect(Socket.java:535)
 W/System.err:     at java.net.Socket.<init>(Socket.java:427)
 W/System.err:     at java.net.Socket.<init>(Socket.java:210)
 W/System.err:     at johnedchristensen.androidclienttestapplication.Client.doInBackground(Client.java:43)
 W/System.err:     at johnedchristensen.androidclienttestapplication.Client.doInBackground(Client.java:19)
 W/System.err:     at android.os.AsyncTask$2.call(AsyncTask.java:304)
 W/System.err:     at java.util.concurrent.FutureTask.run(FutureTask.java:237)
 W/System.err:     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
 W/System.err:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
 W/System.err:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
 W/System.err:     at java.lang.Thread.run(Thread.java:761)

Android应用程序具有互联网和访问网络状态权限，所以我不知道为什么它不会连接到服务器 .