UDP:
need datagramSocket to the middle of the transportation
transport layer protocol connectionless, providing transaction-oriented transport service simply unreliable information may be lost, very simple, small overhead
all to package centered
data transmission without IO streams
Receiving end
Address already in use: Can not bind under the same protocol port can not conflict
1, using DatagramSocket designated port to create a receiving end
2, to prepare a packaged into DatagramPacket package
3, blocking accept packages from the receive (DatagramPacket P);
. 4, analysis data getData () returns a byte array type, getLength () returns the data length, type of int
. 5, the release of resources
public class http {
public static void main(String[]args) throws Exception
{
System.out.println("接收方启动中...");
//1、使用DatagramSocket指定端口 创建接收端
DatagramSocket server=new DatagramSocket(9999);//同一台电脑上端口不要冲突
//2、准备容器封装成DatagramPacket 包裹
byte[] container=new byte[1024*60];
DatagramPacket packet=new DatagramPacket(container,0,container.length);
//3、阻塞式接受包裹receive(DatagramPacket p)；
server.receive(packet);//阻塞式，有等待时间
//4、分析数据getData()返回类型为字节数组，getLength()返回数据长度，类型为int
byte[] datas=packet.getData();
int len=packet.getLength();
System.out.println(new String(datas,0,datas.length));
//5、释放资源
server.close();
}
}The transmitting end
1, the transmitting side created DatagramSocket designated port
2, prepare the data must be converted into a byte array
3, to prepare a packaged DatagramPacket package, requiring a destination (ip address and port)
4, a package sent send (DatagramPacket p );
5, free up resources
public class client {
public static void main(String[]args) throws IOException
{
System.out.println("发送启动中...");
//1、使用DatagramSocket指定端口 创建发送端
DatagramSocket client =new DatagramSocket(8888);
//2、准备数据，一定要转成字节数组
String data="我最帅";
byte[] datas=data.getBytes();
//3、准备容器封装成DatagramPacket 包裹，需要指定目的地（ip地址和端口）
DatagramPacket packet=new DatagramPacket(datas,0,datas.length,new InetSocketAddress("localhost",9999));
//4、发送包裹send(DatagramPacket p)；
client.send(packet);
//5、释放资源
client.close();
}
}