一站式学习Java网络编程 全面理解BIO_NIO_AIO，学习手记（三）

大家好，我是方圆
这里的知识还挺简单的

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1. BIO阻塞模型

简述BIO模型中服务端与客户端的响应过程

1. 服务器serverSocket先要和端口进行绑定
2. 绑定完成后，执行accept方法，等待客户端的连接，这个方法是阻塞式调用，也就是说，要一直等待客户端的连接响应，不做其他事情，一直等，（被阻塞的还有InputStream.read()、OutputStream.write()，这两个也会一直等待客户端的响应）
3. 客户端创建Socket对象，绑定服务器的ip地址与端口号，与服务器进行连接
4. 服务器接收到客户端的连接请求，accept方法获取到客户端的socket信息，连接成功
5. 服务器与客户端创建各自的io流，实现全双工通信
6. 之后便可以随时结束连接

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2. 简单实战演示

2.1 服务器

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;


public class Server {
    
    
    public static void main(String[] args) {
    
    
        final int DEFAULT_PORT = 8888;
        final String QUIT = "quit";
        ServerSocket serverSocket = null;

        try {
    
    
            //绑定端口号
            serverSocket = new ServerSocket(DEFAULT_PORT);
            System.out.println("服务器已经启动，绑定端口号：" + DEFAULT_PORT);

            while (true){
    
    
                //等待客户端的连接
                Socket socket = serverSocket.accept();
                System.out.println("客户端" + socket.getPort() + ":" + "已经连接");

                //获取io流
                BufferedReader reader = new BufferedReader(
                        new InputStreamReader(socket.getInputStream())
                );
                BufferedWriter writer = new BufferedWriter(
                        new OutputStreamWriter(socket.getOutputStream())
                );

                //读取客户发送的信息
                String msg = null;
                while ((msg = reader.readLine()) != null) {
    
    
                    System.out.println("客户端" + socket.getPort() + ":" + msg);
                    //回复消息
                    writer.write( msg + " ok" +"\n");
                    writer.flush();
                    System.out.println("服务器：" + msg + " ok");

                    if(msg.equals(QUIT)){
    
    
                        System.out.println("客户端" + socket.getPort() + ":断开连接" );
                        break;
                    }
                }
            }
        } catch (IOException e) {
    
    
            e.printStackTrace();
        }finally {
    
    
            if(serverSocket != null){
    
    
                try {
    
    
                    serverSocket.close();
                    System.out.println("服务器Socket关闭");
                } catch (IOException e) {
    
    
                    e.printStackTrace();
                }
            }
        }
    }
}

2.2 客户端

import java.io.*;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {
    
    
    public static void main(String[] args) {
    
    
        final int DEFAULT_SERVER_PORT = 8888;
        final String DEFAULT_ADDRESS = "127.0.0.1";
        final String QUIT = "quit";

        Socket socket = null;
        BufferedWriter writer = null;

        try {
    
    
            //创建Socket
            socket = new Socket(DEFAULT_ADDRESS,DEFAULT_SERVER_PORT);

            //创建io流
            writer = new BufferedWriter(
                    new OutputStreamWriter(socket.getOutputStream())
            );
            BufferedReader reader = new BufferedReader(
                    new InputStreamReader(socket.getInputStream())
            );

            //等待用户输入信息
            while (true) {
    
    
                BufferedReader consoleReader = new BufferedReader(new InputStreamReader(System.in));
                String msg = consoleReader.readLine();
                //向服务器发送消息
                writer.write(msg + "\n");
                writer.flush();
                System.out.println("客户端"+ ":" + msg);
                String line = reader.readLine();
                System.out.println("服务器：" + line);
                //退出判断
                if(msg.equals(QUIT)){
    
    
                    break;
                }
            }
        } catch (UnknownHostException e) {
    
    
            e.printStackTrace();
        } catch (IOException e) {
    
    
            e.printStackTrace();
        }finally {
    
    
            if(writer != null){
    
    
                try {
    
    
                    writer.close();
                } catch (IOException e) {
    
    
                    e.printStackTrace();
                }
            }
        }

    }
}

2.3 响应结果

• 客户端
  
• 服务器
  

3. 加深理解

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赶赶单单！