网络编程

TCP/IP——C/S

端口

端口：0～65535
端口分类：公用端口0～1023
1. http：80
2. https：443
3. FTP：21
4. Telent：23
程序注册端口：1024～49151
1. Tomact：8080
2. MySQL：3306
3. Oracle：1521
动态、私有：49152～65535

TCP

客户端

通过Socket连接服务器
发送消息

package com.net.ip;

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;

public class TcpClient {
    public static void main(String[] args) throws IOException {
        //1、需要知道服务器的地址
        InetAddress serverIp = InetAddress.getByName("127.0.0.1");
        //2、端口号
        int port = 9999;
        //3.创建socket链接
        Socket socket = new Socket(serverIp, port);
        //4.发送消息IO流
        OutputStream os = socket.getOutputStream();
        Scanner scanner = new Scanner(System.in);
        System.out.println("客户端输入： ");
        String input = scanner.nextLine();
        os.write(input.getBytes());
    }
}

服务器

IP地址和端口号
创建ServerSoceket
等待用户链接 accept
接收用户的消息

package com.net.ip;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class TcpServer {
    public static void main(String[] args) {
        ServerSocket serverSocket = null;
        Socket accept = null;
        InputStream is = null;
        ByteArrayOutputStream baos = null;
        {
            try {
                //1.需要一个地址
                serverSocket = new ServerSocket(9999);
                //2.等待客户端链接
                accept = serverSocket.accept();
                //3.读取客户端消息
                is = accept.getInputStream();

                //管道流
                baos = new ByteArrayOutputStream();
                byte[] buffer = new byte[1024];
                int len;
                while ((len = is.read(buffer)) != -1){
                    baos.write(buffer,0,len);
                }
                System.out.println(baos.toString());


            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                //关闭资源
                try {
                    baos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    accept.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

文件上传

客户端

package com.net.ip;

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

public class TcpClientDemo1 {
    public static void main(String[] args) throws IOException {
        //1.创建Scoket链接
        Socket socket = new Socket(InetAddress.getByName("localhost"),9999);

        //2.创建一个输出流
        OutputStream outputStream = socket.getOutputStream();

        //3.文件流
        FileInputStream fileInputStream = new FileInputStream("1.png");

        //4.写出文件
        byte[] buffer = new byte[1024];
        int len = 0;
        while (fileInputStream.read(buffer) != -1){
            outputStream.write(buffer,0,len);
        }

        //通知服务器，我已经传输完了
        socket.shutdownOutput();

        //确定服务器接收完毕，才能断开连接
        InputStream is = socket.getInputStream();
        //String byte
        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        byte[] buffer2 = new byte[1024];
        int len2;
        while ((len2=is.read(buffer2))!= -1){
            baos.write(buffer2,0,len2);
        }
        System.out.println(baos.toString());

        //5.关闭资源
        baos.close();
        is.close();
        fileInputStream.close();
        outputStream.close();
        socket.close();
    }
}

服务器

package com.net.ip;

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

public class TcpServerDemo1 {
    public static void main(String[] args) throws IOException {
        //1.创建服务
        ServerSocket serverSocket = new ServerSocket(9999);
        //2.监听客户端的连接
        Socket socket = serverSocket.accept();   //阻塞式监听，会一直等待客户端连接
        //3.获取输入流
        InputStream is = socket.getInputStream();
        //4.文件输出
        FileOutputStream fos = new FileOutputStream(new File("receive.png"));
        byte[] buffer = new byte[1024];
        int len = 0;
        while (is.read(buffer) != -1){
            fos.write(buffer,0,len);
        }

        //通知客户端我接收完毕了
        OutputStream os = socket.getOutputStream();
        os.write("我接收完毕了，你可以断开".getBytes());

        //关闭资源
        fos.close();
        is.close();
        socket.close();
    }
}

Tomcat

sudo sh ./startup.sh 开启

sh ./shutdown.sh 关闭

UDP

发送消息

package com.net.udp;

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

public class UdpDemo1a {
    public static void main(String[] args) throws IOException {
        //1.建立一个Socket
        DatagramSocket socket = new DatagramSocket();

        //2.建个包
        String msg = "你好，服务器";
        InetAddress inetAddress = InetAddress.getByName("localhost");
        int port = 9999;

        //发送给谁
        DatagramPacket datagramPacket = new DatagramPacket(msg.getBytes(),0,msg.getBytes().length,inetAddress,port);

        //3.发送包
        socket.send(datagramPacket);
        //4.关闭流
        socket.close();
    }
}

接收端

package com.net.udp;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
//要等待客户端的连接
public class UdpDemo1b {
    public static void main(String[] args) throws IOException {
        //1.建立一个Scoket
        DatagramSocket socket = new DatagramSocket(9999);

        //2、接收包
        byte[] buffer = new byte[1024];
        DatagramPacket datagramPacket = new DatagramPacket(buffer,0, buffer.length);
        //阻塞接收
        socket.receive(datagramPacket);

        System.out.println(datagramPacket.getAddress());
        System.out.println(new String(datagramPacket.getData(),0,datagramPacket.getLength()));
        //关闭流
        socket.close();
    }
}

循环发送、接收

发送端

package com.net.chat;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.*;

public class UdpD01 {
    public static void main(String[] args) throws IOException {
        //1.创建一个Socket
        DatagramSocket datagramSocket = new DatagramSocket(9999);
        //2.地址信息
        InetAddress inetAddress = InetAddress.getByName("localhost");
        int port = 9998;
        //3.发送的信息
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

        while (true){
            String msg = reader.readLine();
            //4.要发送给谁
            DatagramPacket datagramPacket = new DatagramPacket(msg.getBytes(),0,msg.getBytes().length,inetAddress,port);

            datagramSocket.send(datagramPacket);
            if (msg.equals("bye")){
                break;
            }
        }
        //5.关闭流
        datagramSocket.close();
    }
}

接收端

package com.net.chat;

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

public class UdpD02 {
    public static void main(String[] args) throws IOException {
        DatagramSocket datagramSocket = new DatagramSocket(9998);

        InetAddress inetAddress = InetAddress.getByName("localhost");
        int port = 9999;

        while (true){
            byte[] buffer = new byte[1024];
            DatagramPacket datagramPacket = new DatagramPacket(buffer,0,buffer.length);
            datagramSocket.receive(datagramPacket);

            //断开连接
            byte[] data = datagramPacket.getData();
            String receiveData = new String(data,0, data.length);

            System.out.println(receiveData);

            if (receiveData.equals("bye")){
                break;
            }
        }
        datagramSocket.close();
    }
}

聊天实现

发送

package com.net.chat;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;

public class TalkSend implements Runnable{
    DatagramSocket socket = null;
    BufferedReader reader = null;

    private int fromPort;
    private String toIP;
    private int toPort;

    public TalkSend(int fromPort, String toIP, int toPort) {
        this.fromPort = fromPort;
        this.toIP = toIP;
        this.toPort = toPort;

        try {
            socket = new DatagramSocket(fromPort);
            reader = new BufferedReader(new InputStreamReader(System.in));

        } catch (SocketException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void run() {

        //3.发送的信息

        while (true){
            try {
                String msg = reader.readLine();
                //4.要发送给谁
                DatagramPacket datagramPacket = new DatagramPacket(msg.getBytes(),0,msg.getBytes().length,new InetSocketAddress(this.toIP,this.toPort));
                socket.send(datagramPacket);
                if (msg.equals("bye")){
                    break;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        //5.关闭流
        socket.close();
    }
}

接收

package com.net.chat;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

public class TalkReceive implements Runnable{
    DatagramSocket socket = null;
    private int port;
    private String msgFrom;

    public TalkReceive(int port, String msgFrom) {
        this.port = port;
        this.msgFrom = msgFrom;
        try {
            socket = new DatagramSocket(this.port);
        } catch (SocketException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void run() {
        while (true){
            try {
                byte[] buffer = new byte[1024];
                DatagramPacket datagramPacket = new DatagramPacket(buffer,0,buffer.length);
                socket.receive(datagramPacket);

                //断开连接
                byte[] data = datagramPacket.getData();
                String receiveData = new String(data,0, data.length);

                System.out.println(msgFrom+": "+receiveData);

                if (receiveData.equals("bye")){
                    break;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        socket.close();
    }
}

多线程实现

package com.net.chat;

public class TalkStudent {
    public static void main(String[] args) {
        //开启两个线程,一个发送，一个接收
        new Thread(new TalkSend(7777,"localhost",9999)).start();
        new Thread(new TalkReceive(8888,"老师")).start();
    }

}

package com.net.chat;

public class TalkTeacher {
    public static void main(String[] args) {
        new Thread(new TalkSend(5555,"localhost",8888)).start();
        new Thread(new TalkReceive(9999,"学生")).start();
    }
}

URL

https://www.baidu.com

统一资源定位符

//  协议：//ip地址：端口/项目名/资源

package com.net.url;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class URLDown {
    public static void main(String[] args) throws IOException {
        //1.下载地址
        URL url = new URL("http://localhost:8080/liangzy/lzyscf.txt");

        //2.连接到这个资源
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        InputStream is = urlConnection.getInputStream();

        FileOutputStream fos = new FileOutputStream("URL.txt");
        byte[] buffer = new byte[1024];
        int len = 10;
        while ((len =is.read(buffer) )!= -1){
            fos.write(buffer,0,len);
        }
        fos.close();
        is.close();
        urlConnection.disconnect();
    }
}

用TCP实现聊天功能

posted @ 2021-02-20 17:24 2023不负汗水阅读(81) 评论(0) 收藏举报

刷新页面返回顶部

网络编程

网络编程

端口

TCP

文件上传

Tomcat

UDP

聊天实现

URL

用TCP实现聊天功能

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