16.网络通信

public class InternetServerTest {
    /*
    tcp协议是一种以固定连线为基础的协议 保证数据的可靠传输
    udp是无连接通信协议 不保证数据的传输
    tcp程序基础
    1.服务端创建一个serversocket调用accept方法等待客户端连接
    2.客户端创建一个socket请求与服务端连接
    3.服务端接受连接请求 同时创建一个新的socket等待其他的连接
    InetAddress类与IP地址有关的信息
    Socket套接字 ServerSocket
    * */

    public static void main(String[] args) {
        try {
            ServerSocket server = new ServerSocket(8000);
            System.out.println("服务端套接字创建成功,等待连接");
            Socket socket = server.accept();
            OutputStream os = socket.getOutputStream();
            os.write("服务端收到客户端消息".getBytes());
            InputStream is = socket.getInputStream();
            BufferedReader bf = new BufferedReader(new InputStreamReader(is));
            int length = 0;
            while ((length = bf.read()) != -1) {
                System.out.println((char) length);
            }
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

public class InternetClientTest {

    public static void main(String[] args) {
        try {
            System.out.println("客户端尝试获取连接");
            Socket socket = new Socket("127.0.0.1", 8000);
            OutputStream os = socket.getOutputStream();
            os.write("我是client".getBytes());
            socket.shutdownOutput();
            InputStream is = socket.getInputStream();
            int len=0;
            byte[] bytes=new byte[1024];
            while ((len=is.read(bytes))!=-1){
                System.out.println(new String(bytes,0,len));
            }
        }catch (Exception e){
            e.printStackTrace();
        }

    }
}