Question

它是一个简单的客户端 - 服务器程序，客户端发送文本，服务器在控制台上显示它。这是我的代码：

MyServer的

SELECT * 
FROM fixtures f
LEFT JOIN  fixture_channel_join fcj ON f.fixtures_id = fcj.fixture_id
LEFT JOIN  channel c ON fcj.channel_id = c.id
WHERE f.matchday =  '1'

MyClient

import java.io.*;
import java.net.*;
public class MyServer {
public static void main(String args[]) throws IOException
 {
  ServerSocket socket=new ServerSocket(4444);
  Socket s=socket.accept();
  BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));

 String text;
 while(  (text=in.readLine())!=null)
  {  System.out.println(text);
   } 

 }

MyServer 类中的 readLine（）语句中会出现异常。这是我得到的例外：

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


 public class MyClient {
public static void main(String args[]) throws IOException
{ Socket socket=new Socket("localhost",4444);
PrintWriter out=new PrintWriter(socket.getOutputStream());
out.println("c:/users/pinder/desktop/happy.txt");



 }
 }

Answer 1

SocketException是IOException（位于throws方法的main()条款中。由于您没有正确关闭连接，因此读者投了这个错误，它是由启动器打印的。

如果您在另一端正在读取连接时close()套接字，则您不会收到此错误。 e.g。

public class MyServer {
    public static void main(String args[]) throws IOException {
        try (ServerSocket socket = new ServerSocket(4444);
             Socket s = socket.accept();
             BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()))) {

            String text;
            while ((text = in.readLine()) != null) {
                System.out.println(text);
            }
        }
    }
}
public class MyClient {
    public static void main(String[] args) throws IOException {
        try (Socket socket = new Socket("localhost", 4444);
             PrintWriter out = new PrintWriter(socket.getOutputStream())) {
            out.println("c:/users/pinder/desktop/happy.txt");
        }
    }
}

如果我运行MyServer，然后运行MyClient，服务器将打印

 c:/users/pinder/desktop/happy.txt

客户端无法发送消息

1 个答案: