6-TCP-2022-12-17

编写两个类 

客户端

1、连接服务器

2、发送消息

package Lesson01;

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

public class TcpClientDemo01 {
    public static void main(String[] args) {
        Socket socket = null;
        OutputStream os = null;
        //1.要知道服务器的地址
        try {
            //1.要知道服务器的地址、端口号
            InetAddress serverIP = InetAddress.getByName("127.0.0.1");
            int port = 9999;
            //2.创建一个SOCKET连接
            socket = new Socket(serverIP,port);
            //3.发送消息 I/O流
            os = socket.getOutputStream();
            os.write("你好，我是新的世界".getBytes());

        } catch (Exception e) {
            throw new RuntimeException(e);
        }finally {

            if (os != null) {
                try {
                    os.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }

            if (socket != null) {
                try {
                    socket.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
        }

    }
}

服务器

1、建立服务端口 ServerSocket

2、等待用户的连接 accept

3、接收用户的消息

package Lesson01;

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

public class TcpServerDemo01 {
    public static void main(String[] args) {
        ServerSocket serverSocket = null;
        Socket socket = null;
        InputStream is = null;
        ByteArrayOutputStream baos = null;

        try {
            //1.我得有一个地址
            serverSocket = new ServerSocket(9999);
            while (true) {
                //2.等待客户端连接
                socket = serverSocket.accept();
                //3.读取客户端的消息
                is = socket.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) {
            throw new RuntimeException(e);
        }finally {
            //关闭资源
            if (baos != null) {
                try {
                    baos.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            if (socket != null) {
                try {
                    socket.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            if (serverSocket!=null){
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
        }

    }
}