简单的客户端服务器 Java 程序不进入 while 循环

Question

我在做作业时偶然发现了一个死块。这是一个简单的服务器和客户端程序。 该方案的具体内容如下；

1. 创建一个监听传入连接的服务器类EncryptServer。如果有连接，接受它并创建一个线程EncryptServerSession 来处理输入和输出流。
2. 创建一个线程类EncryptServerSession，从服务器类接收输入和输出流并进行处理。
3. 创建一个客户端类EncryptClient，它连接到服务器类并从EncryptServerSession 到EncryptServer 获取输出流。

不知何故，EncryptClient 类的 while true 循环不起作用。我似乎无法进入循环。我的代码有问题吗？提前致谢。

加密服务器

import java.net.*;
import java.io.*;

public class EncryptServer
{    
    public EncryptServer() throws IOException
    {
         ServerSocket serverSocket = new ServerSocket(1122);
         System.out.println("Server started."); 
     
         while (true)
         {
             Socket conSocket = serverSocket.accept();
             System.out.println("Client connected from " + 
conSocket.getLocalAddress().getHostName()); 
         
             Thread session = new 
EncryptServerSession(conSocket.getInputStream(), 
conSocket.getOutputStream());
             session.start();
         }
    }
    public static void main(String[] args)
    {
        try
        {
            EncryptServer server = new EncryptServer();
        }
        catch (Exception e)
        {
            System.out.println(e);
        }                                      
    }      
}

加密服务器会话

import java.net.*;
import java.io.*;

public class EncryptServerSession extends Thread
{
    BufferedReader in;
    Writer out;

    public EncryptServerSession(InputStream inStream, OutputStream outStream)
    {
        Reader read = new InputStreamReader(inStream);
        in = new BufferedReader(read);
        out = new OutputStreamWriter(outStream);
    }
    
    public void strEncrypt()
    {
        try
        {
            String message = in.readLine();
            out.write(message);
            out.flush();
        }
        catch (Exception e)
        {
        }
    }
    
    public void run()
    {
        try
        {
            //System.out.println(in.readLine());
            out.write("Please enter the message to be encrypted: ");
            out.flush();
            
            //strEncrypt();
        
        }
        catch (Exception e)
        {
            System.out.println(e);
        }        
    }
}

加密客户端

import java.net.*;
import java.io.*;

public class EncryptClient
{
    BufferedReader input, userTerm;
    Writer output;
    String line;
    
    public EncryptClient() throws IOException
    {
        Socket clientSocket = new Socket("localhost", 1122);
        Reader read = new InputStreamReader(clientSocket.getInputStream());
        input = new BufferedReader(read);
        
        userTerm = new BufferedReader(new InputStreamReader(System.in));
        output = new OutputStreamWriter(clientSocket.getOutputStream());             
        
        /////////////// Somehow I cannot get into this loop, why? //////////
        while (true) 
        {
            System.out.println("test ");
            System.out.println(input.readLine());
            System.out.println("Enter message to be encrypted: ");
            output.write(userTerm.readLine());        
            output.flush();
        }
        /////////////// Somehow I cannot get into this loop, why? //////////
    }
    
    public static void main(String[] args)
    {
        try
        {
          EncryptClient client = new EncryptClient();
        }
        catch (Exception e)
        {
            System.out.println(e);
        }
    }
}

Answer 1

据我了解，您正在尝试向服务器发送消息，执行一些逻辑，然后将其发送回客户端。上面的代码似乎在我这边运行良好。这是我所做的：

• 首先运行EncryptServer。我希望这是您面临的问题。或者你的防火墙不允许你监听套接字。

• 在EncryptServerSession 中，您正在阅读行但没有写行。 close 流或完成后写一个新行。

  ...
  
  out.write(message);
  out.write("\r\n"); // write new line
  out.flush();
  
  ...
  
  } finally {
      try {
        out.close();
      } catch (IOException e) {
      }
  }
  

  或

  ...
  
  out.write(message);
  out.write("\r\n"); // write new line
  out.flush();
  
  ...