如何在套接字服务器所在的同一台计算机 (IP) 上运行套接字客户端?

Question

我做了一个简单的聊天，如果在一个IP上运行服务器，在另一个IP上运行客户端，它的工作原理是按设计工作的。此聊天适用于网络。问题是 - 当我尝试在我的计算机上运行服务器时，我的计算机上的客户端不起作用。但是，如果其他具有其他IP的人尝试连接到服务器 - 一切都很好。可能是什么问题？

服务器：

/**
* Created by rnd on 7/4/2017.
*/
import java.io.*;
import java.net.*;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.*;
public class VerySimpleChatServer {
ArrayList clientOutputStreams;
ArrayList<String> m_history;

public static void main (String[] args) {
new VerySimpleChatServer().go();
}
public void go() {
clientOutputStreams = new ArrayList();
m_history = new ArrayList<String>();
try {
ServerSocket serverSock = new ServerSocket(10001);
while(true) {
Socket clientSocket = serverSock.accept();
Charset charset = StandardCharsets.UTF_8;
OutputStreamWriter osw = new OutputStreamWriter( clientSocket.getOutputStream(), charset );
PrintWriter writer = new PrintWriter( new BufferedWriter( osw ) );
//                PrintWriter writer = new PrintWriter(clientSocket.getOutputStream());
writer.println("Welcome to the chat 7 kids.... Семеро Козлят");
writer.flush();
clientOutputStreams.add(writer);
Thread t = new Thread(new ClientHandler(clientSocket));
t.start() ;
System.out.println("got a connection");
}
} catch(Exception ex) {
ex.printStackTrace();
}
} // Закрываем go

public class ClientHandler implements Runnable {
BufferedReader reader;
Socket sock;
public ClientHandler(Socket clientSocket) {
try {
sock = clientSocket;
InputStreamReader isReader = new InputStreamReader(sock.getInputStream(), StandardCharsets.UTF_8);
reader = new BufferedReader(isReader);
} catch(Exception ex) {ex.printStackTrace();}
} // Закрываем конструктор
public void run() {
String message;
tellHistory(m_history);
try {
while ((message = reader.readLine()) != null) {
System.out.println("read " + message);
m_history.add(message);
tellEveryone(message);
} // Закрываем while
} catch(Exception ex) {ex.printStackTrace();}
} // Закрываем run
} // Закрываем вложенный класс


public void tellEveryone(String message) {
Iterator it = clientOutputStreams.iterator();
while(it.hasNext()) {
try {
PrintWriter writer = (PrintWriter) it.next();
writer.println(message);
writer.flush();
} catch(Exception ex) {
ex.printStackTrace();
}
} // Конец цикла while
} // Закрываем tellEveryone
public void tellHistory(ArrayList<String> history){

try {
PrintWriter writer1 = (PrintWriter) clientOutputStreams.get(clientOutputStreams.size() - 1);
for (int i = 0; i < history.size(); i++) {
writer1.println(history.get(i));
}
//Идея в том, что бы вызывать историю только для последнего PrintWriter
//может быть getsize поставить вместо i - writer1.println(history.get(history.size()));
writer1.flush();
} catch(Exception ex) {
ex.printStackTrace();
}

}
} // Закрываем класс

客户：

/**
* Created by rnd on 7/4/2017.
*/
import java.io.*;
import java.net.*;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class SimpleChatClient {
JTextArea incoming;
JTextField outgoing;
JTextField name;
BufferedReader reader;
PrintWriter writer;
Socket sock;
String Myname;

public static void main(String[] args) {
SimpleChatClient client = new SimpleChatClient();
client.go();}
public void go(){
JFrame frame = new JFrame("Ludicrously Simple Chat Client");
JPanel mainPanel = new JPanel();
incoming = new JTextArea(15,50);
incoming.setLineWrap(true);
incoming. setWrapStyleWord (true) ;
incoming.setEditable(false);
JScrollPane qScroller = new JScrollPane(incoming);
qScroller. setVerticalScrollBarPolicy (ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS) ;
qScroller. setHorizontalScrollBarPolicy (ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS) ;
outgoing = new JTextField(20);
name = new JTextField(5);
JButton sendButton = new JButton("Send") ;
JLabel label1 = new JLabel("name");
sendButton.addActionListener(new SendButtonListener());
mainPanel.add(qScroller);
mainPanel.add(label1);
mainPanel.add(name);
mainPanel.add(outgoing);
mainPanel.add(sendButton);
setUpNetworking();
Thread readerThread = new Thread(new IncomingReader());
readerThread.start();
frame.getContentPane().add(BorderLayout.CENTER, mainPanel);
frame.setSize(800,500);
frame.setVisible(true);
}
private void setUpNetworking() {
try {
sock = new Socket("178.165.87.221", 10001);
//            sock = new Socket("127.0.0.1", 10001);
InputStreamReader streamReader = new InputStreamReader(sock.getInputStream(), StandardCharsets.UTF_8 );
reader = new BufferedReader(streamReader);

Charset charset = StandardCharsets.UTF_8;
OutputStreamWriter osw = new OutputStreamWriter( sock.getOutputStream(), charset );
writer = new PrintWriter( new BufferedWriter( osw ) );
//            writer = new PrintWriter(sock.getOutputStream());
System.out.println("networking established");
} catch (IOException ex) {
ex.printStackTrace();}
}
public class SendButtonListener implements ActionListener {
public void actionPerformed (ActionEvent ev) {
try {
Myname = name.getText();
writer.println(Myname + ": " + outgoing.getText());
writer.flush();
} catch(Exception ex) {
ex.printStackTrace();
}
outgoing. setText ("") ;
outgoing.requestFocus () ;}
}
public class IncomingReader implements Runnable{
@Override
public void run() {
String message;
try{
while((message=reader.readLine())!=null ){
System.out.println("read " + message);
incoming.append(message + "n");
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
}

Answer 1

这是178.165.87.221服务器机器的本地IP吗？ 本地 就像您在终端中运行ipconfig或ifconfig一样，您将看到此 IP,,, 如果要在同一台机器上运行服务器和客户端，客户端应使用服务器的本地IP，

如果您不知道本地 IP，可以使用localhost或127.0.0.1

因此，客户端代码应该是其中之一：

sock = new Socket("127.0.0.1", 10001); //localhost alias

或

sock = new Socket("localhost", 10001); //localhost alias

或

sock = new Socket("192.168.100.10", 10001); // local IP [machine local IP might be something else, this is only an example]

注意：178.165.87.221看起来像一个真实IP，如果你想在客户端中使用它，而与服务器在同一台机器上，你可能希望配置你的路由器/网络防火墙/操作系统防火墙，以允许/转发聊天系统端口到服务器机器的本地IP