Question

Java编程的socket编程问题，出现 java.net.ConnectException的错误，请问该如何改正程序。谢谢！

import java.io.*;

import java.net.*;

public class comm {

/**

* @param args

* @throws IOException

*/

public static void main(String[] args) throws IOException {

// TODO Auto-generated method stub

Socket echoSocket = null;

PrintWriter out = null;

BufferedReader in = null ;

try{

echoSocket = new Socket ("localhost" , 8001);

out = new PrintWriter(echoSocket .getOutputStream(),true);

in = new BufferedReader (new InputStreamReader (echoSocket.

getInputStream()));

}

catch (UnknownHostException e){

System .err .println("找不到服务器:localhost !");

System .exit(1);

}

System .out.println(in.readLine());

System .out.println(in.readLine());

BufferedReader stdIn = new BufferedReader(new InputStreamReader(System .in));

String userInput;

while ((userInput = stdIn.readLine())!= null){

out.println(userInput);

System.out .println(in.readLine());

out.close();

in .close();

echoSocket .close();

}

ServerSocket serverSocket = null;

out = null;

in = null ;

try{

serverSocket = new ServerSocket(8001);

}

catch (IOException e){

System.err .println("不能监听端口:8001.");

System.exit(1);

}

Socket incoming = null;

while(true)

{

incoming = serverSocket.accept();

out = new PrintWriter (incoming .getOutputStream (),

true);

in =new BufferedReader(new InputStreamReader(incoming

.getInputStream()));

out.println(" 你好! …");

out.println("输入Exit 退出。");

out.flush();

while(true){

String str = in.readLine();

if(str == null){

break;

}

else{

out .println(" 服务器给客户端:"+str);

out .flush();

if(str .trim().equalsIgnoreCase("Exit")){

break;

}

}

out.close();

in .close();

serverSocket .close();

}

}

}

}

Answer 1

serverSocket没有创建起来，所以你的cilentSocket去连接的时候就会这样报错。
你运行 cmd-netstat -nao 看下你serverSocket所监听的端口有没有存在。

追问

请问要怎么创建呢？试了好几个端口都不行。