如何在本地主机中创建套接字和ServerSocket？

Question

我第一次使用eclipse，socket和ServerSocket在笔记本电脑上设置本地主机，并且在编译器上收到错误消息：

Exception in thread "main" java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at server.Cli.main(Cli.java:15)

这是为我自己的个人发展，我尝试使用不同的数字进行尝试，但是我不知道该行中的数字是什么或在哪里起源的：s = new Socket（“ 127.0.0.1”，1342）; 有关我的代码片段的任何信息或有关如何制作成功代码的帮助，将不胜感激。我只是自己学习有关内容，并想知道它可以带给我什么。

package server;

import java.io.IOException;
import java.io.PrintStream;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;

public class Cli {

 public static void main(String[] args) throws UnknownHostException, 
           IOException {
    int number, temp;
    Scanner sc1 = new Scanner(System.in);
    Socket s = new Socket("127.0.0.1", 1342);
    System.out.println("Enter any number");
    number = sc1.nextInt();
    PrintStream p = new PrintStream(s.getOutputStream());
    p.println(number);
    temp = sc1.nextInt();
    System.out.println(temp);
}
}


package server;

import java.io.IOException;
import java.io.PrintStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

public class SimpleHTTPServer {
    public static void main(String args[] ) throws IOException { 
    int number, temp;
    ServerSocket s1 = new ServerSocket(1342);
    Socket ss = s1.accept();
    Scanner sc = new Scanner(ss.getInputStream());
    number = sc.nextInt();
    temp = number * 2;
    PrintStream p = new PrintStream(ss.getOutputStream());
    p.println(temp);
}
}