JavaSE进阶--网络编程

TCP通信

TCP聊天器

Server端

package Socket.demo02;

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

public class server {
    public static void main(String args[])  {
        System.out.println("----------server 启动---------------");
        ServerSocket serverSocket = null;
        Socket socket = null;
        InputStream is = null;
        ByteArrayOutputStream baos = null;
        try{
            serverSocket = new ServerSocket(9997);
            while(true){ socket = serverSocket.accept();
            is = socket.getInputStream();
            //管道流，解决中文输出，显示错误的问题
            baos = new ByteArrayOutputStream();
            byte[] buffer = new byte[1024];
            int len;
            while ((len = is.read(buffer)) != -1) {
                baos.write(buffer, 0, len);
            }
            System.out.println("收到："+baos.toString());
            }
        }catch (IOException e){
                e.printStackTrace();
            }
        finally {
                if(baos!=null){
                    try {
                        baos.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if(is!=null){
                    try {
                        is.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (socket!=null){
                    try {
                        socket.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
    }
}

Client端

package Socket.demo02;

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

public class client {
    public static void main(String[] args){
        System.out.println("----------client 启动---------------");
        Socket socket = null;
        OutputStream os = null;
        try {
            InetAddress serverIP =InetAddress.getByName("127.0.0.1");
            int port = 9997;
            socket = new Socket(serverIP,port);
            os = socket.getOutputStream();
            os.write("你好，客户端正在发送消息".getBytes());// 发送消息
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(os!=null){
                try {
                    os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(socket!=null){
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}

模拟文件上传

package Socket.demo03;

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

public class FileServer {
    public static void main(String[] args) throws IOException {
        System.out.println("---------file server------------");
        ServerSocket serverSocket = new ServerSocket(9000);
        Socket socket = serverSocket.accept();
        InputStream is = socket.getInputStream();
        FileOutputStream fos = new FileOutputStream(new File("girl2.png"));
        byte[] buffer = new byte[1024];
        int len;
        while((len=is.read(buffer))!=-1){
            fos.write(buffer,0,len);
        }
        //通知客户端
        OutputStream os = socket.getOutputStream();
        os.write("接收完毕，可以断开..".getBytes());
        fos.close();
        is.close();
        socket.close();
        serverSocket.close();
    }
}

package Socket.demo03;


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

public class FileClient {
    public static void main(String[] args) throws IOException {
        System.out.println("---------file client------------");
        Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9000);    // 创建socket连接//ctr + alt +v
        OutputStream os = socket.getOutputStream();  // 创建一个输出流
        FileInputStream fis = new FileInputStream(new File("girl.png"));   //读取文件
        byte[] buffer = new byte[1024];    //写文件
        int len;
        while((len=fis.read(buffer))!=-1){
            os.write(buffer,0,len);
        }
        //通知服务器传输完毕
        socket.shutdownOutput();
        //确定服务器接收完毕，才能断开
        InputStream is = socket.getInputStream();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buf = new byte[1024];
        int len2;
        while((len2=is.read(buf))!=-1){
            baos.write(buf,0,len2);
            System.out.println(baos.toString());
        }

        is.close();
        baos.close();
        fis.close();
        os.close();
        socket.close();
    }
}

UDP通信

UDP消息发送

接收接收端

package Socket.demo04;

import java.net.DatagramPacket;
import java.net.DatagramSocket;


public class udpServer {
    public static void main(String[] args) throws Exception {
        DatagramSocket socket = new DatagramSocket(9090);
        byte[] buffer = new byte[1024];
        DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length);
        socket.receive(packet);
        System.out.println(packet.getAddress().getHostAddress());
        System.out.println(new String(packet.getData(),0,packet.getLength()));
        socket.close();
    }
}

发送端

package Socket.demo04;

import java.net.*;

public class udpClient {
    public static void main(String[] args) throws Exception {
        DatagramSocket socket = new DatagramSocket();

        String msg ="你好服务器";
        InetAddress ip = InetAddress.getByName("localhost");
        int port = 9090;
        DatagramPacket packet = new DatagramPacket(msg.getBytes(), 0, msg.getBytes().length, ip, port);

        socket.send(packet);

        socket.close();
    }
}

UDP聊天实现+多线程

TalkSend 发数数据线程

package Socket.demo06;

import java.io.BufferedReader;
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 {

    private int fromPort;
    private String toIP;
    private int toPort;
    DatagramSocket socket = null;
    BufferedReader reader = null;

    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() {
        while(true){
            try{
                String data = reader.readLine();
                byte[] buffer  = data.getBytes();
                DatagramPacket packet = new DatagramPacket(buffer,0, buffer.length,new InetSocketAddress(this.toIP,this.toPort));
                socket.send(packet);
                if(data.equals("bye")){
                    break;
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        socket.close();
    }
}

TalkRecieve 收数据线程

package Socket.demo06;

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

public class TalkReceive implements Runnable {

    private int port;
    private String msgFrom;
    DatagramSocket socket = null;

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

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

                byte[] data = packet.getData();
                String recievedata= new String(data,0,data.length);
                System.out.println(msgFrom + ":" + recievedata);
                if(recievedata.equals("bye")){
                    break;
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        socket.close();
    }
}

学生端

package Socket.demo06;

public class TalkStudent {
    public static void main(String[] args) {
        new Thread(new TalkSend(7777,"localhost",9999)).start();
        new Thread(new TalkReceive(8888,"老师")).start();

    }
}

老师端

package Socket.demo06;

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();

    }
}