reverse.java

Java网络编程应用：包括简易聊天程序的客服端和服务器端的源代码

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

public class Reverse {
   public static void main(String[] args) {
     if (args.length!=1) {
        System.err.println("用法：java Reverse \"这里是一个字符串\"");
        System.exit(1);
     }
     String sendMessage=URLEncoder.encode(args[0]);
     try {
      URL url=new URL("http://java.sun.com/cgi-bin/backwards");
      URLConnection channel=url.openConnection( );
      channel.setDoOutput(true);
      PrintWriter out=new PrintWriter(channel.getOutputStream( ));
      out.println("string="+sendMessage);//输出信息
      out.close( );
      InputStreamReader urlStream=new InputStreamReader(channel.getInputStream());
      BufferedReader in=new BufferedReader(urlStream);
      String getMessage;
      while ((getMessage=in.readLine( ))!=null)  //读取信息
      System.out.println(getMessage);
      in.close( );
      urlStream.close( );
    } 
    catch (MalformedURLException e) {
      System.err.println("无法建立URL");
      System.exit(1);
    } 
    catch (IOException e) {
      System.err.println("无法和服务器通信");
      System.exit(1);
    }
  }
}