JavaTCP网络通信协议详细讲解

//向指定ip发送信息
public static void main(String[] args) throws Exception{
    Socket s=new Socket(InetAddress.getByName(InetAddress.getLocalHost().getHostAddress()),10000);
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    //封装输出流对象
    BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
    String line;
    while (true) {
        if ((line=br.readLine())!=null){
            if("1024".equals(line)) {
                bw.write(line);
                bw.newLine();
                break;
            }
            bw.write(line);
            bw.newLine();
        }
        bw.flush();
        //获取输出流对象
    }
    //释放资源
    s.close();
}

//接收发送到本机的信息
ServerSocket socket=new ServerSocket(10000);
Socket accept = socket.accept();
BufferedReader br = new BufferedReader(new InputStreamReader(accept.getInputStream()));
String line;
while ((line=br.readLine())!=null){
    System.out.println(line);
}

//创建发送端的Socket对象(DatagramSocket)
//创建数据，并把数据打包
//DatagramPacket(byte[] buf, int length, InetAddress address, int port)
//构造一个数据包，发送长度为 length的数据包到指定主机上的指定端口号。

DatagramSocket ds = new DatagramSocket();
byte[] bys = "hello,udp,我来了".getBytes();
        DatagramPacket dp = new DatagramPacket(bys,bys.length,  InetAddress.getByName("10.102.13.18"),10086);
        //调用DatagramSocket对象的方法发送数据
        //void send(DatagramPacket p) 从此套接字发送数据报包
        ds.send(dp);
        System.out.println("已发送："+new String(dp.getData(),0,dp.getLength()));
        //关闭发送端
        //void close() 关闭此数据报套接字
        ds.close();

DatagramSocket ds = new DatagramSocket(10086);
while (true) {
    //创建一个数据包，用于接收数据
    byte[] bys = new byte[1024];
    DatagramPacket dp = new DatagramPacket(bys, bys.length);
    //调用DatagramSocket对象的方法接收数据
    ds.receive(dp);
    System.out.println("-----");
    //解析数据包，并把数据在控制台显示
    System.out.println("数据是：" + new String(dp.getData(), 0, dp.getLength()));
}