6 TCP

package Internet;

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

// 服务端 ：先有服务端再有客户端
public class Test16_Server {
    public static void main(String[] args) throws IOException {
        // 1. 得有一个地址(ServerSocket:服务端)
        ServerSocket serverSocket=new ServerSocket(9999);
        // 2.等待客户端连接
        Socket socket=serverSocket.accept();  // 两个插座的端口号一样，所以两个插座是一样的
        // 3. 读取客户端消息
        InputStream is = socket.getInputStream();
        // 4. 输出客户端信息
        byte[] buffer = new byte[1024];
        int length;
        while ( ( length= is.read(buffer) )  != -1){
            String msg=new String(buffer,0,length);
            System.out.println(msg);
        }
    }
}




//////////////
package Internet;

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

// 客户端
public class Test16_Client {
    public static void main(String[] args) throws IOException {
        // 1. 知道服务器(服务端)的IP和端口号
        InetAddress serverIP = InetAddress.getByName("127.0.0.1");
        int port = 9999;
        // 2. 创建socket（插座）连接
        Socket socket=new Socket(serverIP,port);
        // 3. 发送消息，IO流
        OutputStream os=socket.getOutputStream();
        os.write("学习网络编程".getBytes());
        // 4.关闭
        os.close();
        socket.close();
    }
}