java Socket编程，多线程异步编程

比眉伴天荒 2022-06-09 05:54 218阅读 0赞

最近在学习分布式，分布式的前提是要知道网络服务器的通信，自己对这一块基本不了解，最近学习了一下，整理一个demo，方便以后查阅

这个是关于TCP/BIO，所谓BIO就是阻塞IO，没收到消息时就处于阻塞状态，有消息就工作，我用了多线程来处理收消息和发消息，实现了异步发送

服务器端代码：

![复制代码][copycode.gif]

1 package internetCommunication;
     2 
     3 import java.io.BufferedReader;
     4 import java.io.IOException;
     5 import java.io.InputStreamReader;
     6 import java.io.PrintWriter;
     7 import java.net.ServerSocket;
     8 import java.net.Socket;
     9 
    10 public class Server {
    11 
    12     public static void main(String[] args) {
    13         try {
    14             ServerSocket server = new ServerSocket(8888);
    15             Socket client = server.accept();
    16             BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
    17             PrintWriter out=new PrintWriter(client.getOutputStream());
    18             BufferedReader userin = new BufferedReader(new InputStreamReader(System.in));
    19             
    20             
    21             new ReceiveTread(server,in,out,userin,client).start();
    22             new SendThread(out, userin,true).start();
    23         } catch (IOException e) {
    24             e.printStackTrace();
    25         }
    26         
    27         
    28     }
    29 
    30 }

![复制代码][copycode.gif]

客户端代码

![复制代码][copycode.gif]

1 package internetCommunication;
     2 
     3 import java.io.BufferedReader;
     4 import java.io.IOException;
     5 import java.io.InputStreamReader;
     6 import java.io.PrintWriter;
     7 import java.net.InetAddress;
     8 import java.net.Socket;
     9 
    10 public class Client {
    11     
    12     
    13     public static void main(String[] args) {
    14         try {
    15             Socket server = new Socket(InetAddress.getLocalHost(), 8888);
    16             BufferedReader in = new BufferedReader(new InputStreamReader(server.getInputStream()));
    17             PrintWriter out=new PrintWriter(server.getOutputStream());
    18             BufferedReader userin = new BufferedReader(new InputStreamReader(System.in));
    19             
    20             new SendThread(out,userin,false).start();
    21             new ReceiveTread(server,in,out,userin).start();
    22             
    23             
    24         } catch (IOException e) {
    25             e.printStackTrace();
    26         }
    27         
    28         
    29     }
    30 }

![复制代码][copycode.gif]

发消息多线程类

![复制代码][copycode.gif]

1 package internetCommunication;
     2 
     3 import java.io.BufferedReader;
     4 import java.io.IOException;
     5 import java.io.PrintWriter;
     6 import java.text.SimpleDateFormat;
     7 import java.util.Date;
     8 
     9 public class SendThread extends Thread{
    10 
    11     PrintWriter out;
    12     BufferedReader userin;
    13     boolean isServer;
    14     
    15     public SendThread(PrintWriter out,BufferedReader userin,boolean isServer) {
    16         this.out = out;
    17         this.userin = userin;
    18         this.isServer = isServer;
    19     }
    20 
    21     @Override
    22     public void run() {
    23         SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    24         
    25         try {
    26             while(true){
    27                 if(isServer){
    28                     out.println("Server  "+sf.format(new Date())+"\n\t"+ userin.readLine());
    29                 }else{
    30                     out.println("client  "+sf.format(new Date())+"\n\t"+ userin.readLine());
    31                 }
    32                 out.flush();
    33             }
    34         } catch (IOException e) {
    35             e.printStackTrace();
    36         }
    37         
    38     }
    39     
    40     
    41     
    42     
    43     
    44     
    45 }

![复制代码][copycode.gif]

接消息多线程类

![复制代码][copycode.gif]

1 package internetCommunication;
     2 
     3 import java.io.BufferedReader;
     4 import java.io.IOException;
     5 import java.io.PrintWriter;
     6 import java.net.ServerSocket;
     7 import java.net.Socket;
     8 
     9 public class ReceiveTread extends Thread{
    10     BufferedReader in ;
    11     ServerSocket server;
    12     PrintWriter out;
    13     BufferedReader userin;
    14     Socket client;
    15     
    16     
    17     public ReceiveTread(ServerSocket server,BufferedReader in,PrintWriter out,BufferedReader userin,Socket client) {
    18         this.in = in;
    19         this.server = server;
    20         this.client = client;
    21         this.out = out;
    22         this.userin = userin;
    23     }
    24     
    25     public ReceiveTread(Socket client ,BufferedReader in,PrintWriter out,BufferedReader userin) {
    26         this.in = in;
    27         this.client = client;
    28         this.out = out;
    29         this.userin = userin;
    30     }
    31     
    32     
    33     @Override
    34     public void run() {
    35         try {
    36             while(true){
    37                 String info = in.readLine();
    38                 while(info !=null){
    39                     System.out.println(info);
    40                     info = in.readLine();
    41                 }
    42                 if(in.readLine().equals("end")){
    43                     break;
    44                 }
    45             }
    46             in.close();
    47             out.close();
    48             userin.close();
    49             if(client != null){
    50                 client.close();
    51             }
    52             server.close();
    53         } catch (IOException e) {
    54             e.printStackTrace();
    55         }
    56     }
    57 }

![复制代码][copycode.gif]

以下是控制输出：

这是客户端的

![2012092814042692.jpg][]

这是服务器的：

![2012092814045248.jpg][]

这里要注意的是： 1、启动时要先启动服务器，在启动客户端，因为只有服务器启动了，开始监听某个端口，客户端才能连上

2、因为输入控制台和输出控制台都揉在一起显示，控制台显示接收消息的时候，光标还是会停留在上一次输入的地方，如果输入非汉字类的，光标会自动跳下来

但是输入汉字，会出现把接收到消息也发送的情况，所以需要输入的时候将光标自己点下来，如果是GUI编程的话，就没有这个问题，因为输入的面板和显示面板是独立开来的，呵呵

[copycode.gif]: /images/20220609/90d17925c4704017943d3425b33d9be7.png
[2012092814042692.jpg]: /images/20220609/241fd29c82b14abfb802c60a2ee04572.png
[2012092814045248.jpg]: /images/20220609/062f602c78c64298ace16ea67add2cb2.png