UDP收发消息
udp协议使用数据报套接字，无需建立链接
//send
public class Udp_Send_01 {
public static void main(String[] args) throws IOException {
DatagramSocket socket=new DatagramSocket();
InetAddress add=InetAddress.getByName("localhost");
int port=9090;
String msg="你好啊";
DatagramPacket data=new DatagramPacket(msg.getBytes(), 0,msg.getBytes().length,add,port);
socket.send(data);
socket.close();
}
}
//receive
public class Udp_Receiver_01 {
public static void main(String[] args) throws IOException {
DatagramSocket socket=new DatagramSocket(9090);
byte[] bytes=new byte[1024];
DatagramPacket packet=new DatagramPacket(bytes, 0,bytes.length);
socket.receive(packet);//阻塞接收
System.out.println(packet.getAddress());
System.out.println(new String(packet.getData(),0,packet.getData().length));
socket.close();
}
}
/*************************循环发送，接收*************************/
public class Sender_01 {
public static void main(String[] args) throws IOException {
DatagramSocket socket=new DatagramSocket(8888);
BufferedReader reader=new BufferedReader(new InputStreamReader(System.in));
String data;
byte[] bytes;
while(!(data=reader.readLine()).equals("bye")) {
bytes=data.getBytes();
DatagramPacket pack=new DatagramPacket(bytes,0,bytes.length,new InetSocketAddress("localhost", 6666));
socket.send(pack);
}
socket.close();
}
}
//
public class Receiver_01 {
public static void main(String[] args) throws IOException {
DatagramSocket socket=new DatagramSocket(6666);
byte[] bytes=new byte[1024];
DatagramPacket packet=new DatagramPacket(bytes, 0,bytes.length);
while(true) {
socket.receive(packet);
String msg=new String(packet.getData(),0,packet.getData().length);
if(msg.equals("bye")) {
break;
}
System.out.println(msg);
}
socket.close();
}
}
建立一个通用收发线程实现全双工收发
//发送消息线程
public class Sendmsg implements Runnable{
DatagramSocket socket=null;
BufferedReader reader=null;
private int fromport;
private String toip;
private int toport;
private String name;
public Sendmsg(int fromport,String toip,int toport,String name) throws SocketException, UnknownHostException {
// TODO Auto-generated constructor stub
this.fromport=fromport;
this.toip=toip;
this.toport=toport;
this.name=name;
socket=new DatagramSocket(this.fromport);
reader=new BufferedReader(new InputStreamReader(System.in));
}
@Override
public void run() {
// TODO Auto-generated method stub
String data;
byte[] bytes;
try {
while(!(data=reader.readLine()).equals("bye")) {
bytes=(name+":"+data).getBytes();
DatagramPacket pack=new DatagramPacket(bytes,0,bytes.length,new InetSocketAddress(this.toip, this.toport));
socket.send(pack);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
reader.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
socket.close();
}
}
//接收消息线程
public class Receivemsg implements Runnable{
DatagramSocket socket=null;
private int port;//从此端口接收消息
public Receivemsg(int port) throws SocketException {
// TODO Auto-generated constructor stub
this.port=port;
socket=new DatagramSocket(this.port);
}
@Override
public void run() {
// TODO Auto-generated method stub
byte[] bytes=new byte[1024];
DatagramPacket packet=new DatagramPacket(bytes, 0,bytes.length);
while(true) {
try {
socket.receive(packet);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String msg=new String(packet.getData(),0,packet.getData().length);
if(msg.equals("bye")) {
break;
}
System.out.println("address:"+packet.getAddress()+" "+msg);
}
socket.close();
}
}
//新建两个类的收发线程
public class Student {
public static void main(String[] args) throws SocketException, UnknownHostException {
new Thread(new Sendmsg(6666, "localhost", 8888, "student")).start();
new Thread(new Receivemsg(7777)).start();
}
}
public class Teacher {
public static void main(String[] args) throws SocketException, UnknownHostException {
new Thread(new Sendmsg(5555, "localhost", 7777, "teacher")).start();
new Thread(new Receivemsg(8888)).start();
}
}